Solution 1 :

In your example you have padding that messes up.
Here is a fixed version, added/removed lines are marked:

.skills-display {
    width: 50%;
    /* height: 100px;
    border: 2px solid black; */
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

.skill-progress-bar {
    width: 10rem;
    height: 2rem;
    
/*    padding: 10px 10px 20px 10px; */ /* removed */
    margin: 10px;                       /* added */
    line-height: 2rem;                 /* added, this will center the content*/
    /* border: 1px solid black; */
    border-radius: 0.8rem;
    background-color: lightgrey;
}

.eighty-percent {
    width: 80%;
                                       /* removed */
/*    height: 100%;
    border-radius: 20px 0px 0px 20px;*/

    background-color: orange;
}

.skill-name span {
    color: white;
    font-size: 1rem;
    margin-left: 10px;
}

.twenty-percent {
    width: 20%;
                                       /* removed */
/*    height: 100%;
    border-radius: 20px 0px 0px 20px;*/
    background-color: #2857a4;
}

.seventy-percent {
    width: 70%;
                                       /* removed */
/*    height: 100%;
    border-radius: 20px 0px 0px 20px;*/
    background-color: #20ebb8;
}

.ninety-percent {
    width: 90%;
                                       /* removed */
/*    height: 100%;
    border-radius: 20px 0px 0px 20px;*/
    background-color: rgb(252, 220, 0);
}


                                       /* added */
.skill-progress-bar
{
    overflow: hidden; /* this will hide box-shadow from child element on edges that touching it's parent (aka only show it on right side) */
}

.skill-progress-bar,
.skill-progress-bar > div
{
    box-shadow: 1px 0 7px grey;
}
.skill-progress-bar > div
{
    height: 100%;
 /* border-radius: 0.8rem 0px 0px 0.8rem; */  /* this is unnecessary because we are hiding overflow */
}
<section id="skills">
                <h1 class="section-heading mb75px">
                    <span>
                        <i
                            class="fa-solid fa-chalkboard-user"
                        ></i>
                    </span>
                    <span>SKILLS</span>
                </h1>
                <div class="skills-display">
                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>HTML</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="twenty-percent">
                            <div class="skill-name">
                                <span>C++</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="seventy-percent">
                            <div class="skill-name">
                                <span>Python</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="ninety-percent">
                            <div class="skill-name">
                                <span>JavaScript</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div
                            class="ninety-percent"
                            style="background-color: #43853d"
                        >
                            <div class="skill-name">
                                <span>NodeJS</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>Express</span>
                            </div>
                        </div>
                    </div>
                </div>
            </section>

Solution 2 :

You were adding the shadow on the percentage but it should be on the progress-bar itself (parent container to the variable percentage), if needed. I fixed some of the issues and added comments over the changes made.
Also,removed box-shadow from eighty percent as it made it look uglier and if needed you should add it on the progress bar

Added a background color for the page to this and this should look exactly like your page. You can check out the changes made below

.skills-display {
    width: 50%;
    /* height: 100px;
    border: 2px solid black; */
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

/* Made changes here */
.skill-progress-bar {
    width: 10rem;
    height: 2rem;
    margin-bottom:10px;
    /* border: 1px solid black; */
   /* border-radius: 0.8rem; */
     border-radius: 20px;
    background-color: lightgrey;
    border:0.8px solid grey;
    /*box-shadow: 0 1px 7px 0  grey;*/
}

.eighty-percent {
    width: 80%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;

    background-color: orange;
    /*box-shadow: 1px 0 7px grey;*/
}

/* Added new changes here */
.skill-name{
display:flex;
align-items:center;
height:100%;
}

.skill-name span {
    color: white;
    font-size: 1rem;
    margin-left: 10px;
}

.twenty-percent {
    width: 20%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #2857a4;
}

.seventy-percent {
    width: 70%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #20ebb8;
}

.ninety-percent {
    width: 90%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: rgb(252, 220, 0);
}
<section id="skills">
                <h1 class="section-heading mb75px">
                    <span>
                        <i
                            class="fa-solid fa-chalkboard-user"
                        ></i>
                    </span>
                    <span>SKILLS</span>
                </h1>
                <div class="skills-display">
                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>HTML</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="twenty-percent">
                            <div class="skill-name">
                                <span>C++</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="seventy-percent">
                            <div class="skill-name">
                                <span>Python</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="ninety-percent">
                            <div class="skill-name">
                                <span>JavaScript</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div
                            class="ninety-percent"
                            style="background-color: #43853d"
                        >
                            <div class="skill-name">
                                <span>NodeJS</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>Express</span>
                            </div>
                        </div>
                    </div>
                </div>
            </section>

Solution 3 :

For the shadow i wrap your bars again. (class new). I commented in my code what is new.

.skills-display {
    width: 50%;
    /* height: 100px;
    border: 2px solid black; */  
    display: flex;
    flex-wrap: wrap;
    justify-content: center; /* new */
    gap: 20px; /* new */
}

.skill-progress-bar {
    width: 10rem;
    height: 2rem;
    padding: 10px 10px 20px 10px;
    /* border: 1px solid black; */
    border-radius: 0.8rem;
    background-color: lightgrey;  
}

.eighty-percent {
    width: 80%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: orange;    
}

.skill-name span {
    color: white;
    font-size: 1rem;
    margin-left: 10px;
}

.twenty-percent {
    width: 20%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #2857a4;
    box-shadow: 1px 0 7px grey;
}

.seventy-percent {
    width: 70%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #20ebb8;
}

.ninety-percent {
    width: 90%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: rgb(252, 220, 0);
}

/* new */
.skills-display {
  margin: 0 auto;
}
.section-heading {
  text-align: center;
}

.new {
  background-color: #999;
  border-radius: 20px;
  height: 40px;  
}

.skill-name {
  padding-top:9px;
}
<section id="skills">
                <h1 class="section-heading mb75px">
                    <span>
                        <i
                            class="fa-solid fa-chalkboard-user"
                        ></i>
                    </span>
                    <span>SKILLS</span>
                </h1>
                <div class="skills-display">
                  
                    <div class="skill-progress-bar">
                      <div class="new">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>HTML</span>
                            </div>
                        </div>
                      </div>
                    </div>

                    <div class="skill-progress-bar">
                      <div class="new">
                          <div class="twenty-percent">
                              <div class="skill-name">
                                  <span>C++</span>
                              </div>
                          </div>
                      </div>
                    </div>

                    <div class="skill-progress-bar">
                      <div class="new">
                        <div class="seventy-percent">
                            <div class="skill-name">
                                <span>Python</span>
                            </div>
                        </div>
                      </div>
                    </div>

                    <div class="skill-progress-bar">
                      <div class="new">
                        <div class="ninety-percent">
                            <div class="skill-name">
                                <span>JavaScript</span>
                            </div>
                        </div>
                      </div>
                    </div>

                    <div class="skill-progress-bar">
                      <div class="new">
                        <div
                            class="ninety-percent"
                            style="background-color: #43853d"
                        >
                            <div class="skill-name">
                                <span>NodeJS</span>
                            </div>
                        </div>
                      </div>
                    </div>

                    <div class="skill-progress-bar">
                      <div class="new">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>Express</span>
                            </div>
                        </div>
                      </div>
                    </div>
                </div>
            </section>

Problem :

I am making a resume for an assignment. I have pretty much completed everything, but i cant add shadow to skills section as required for some reason, maybe i dont understand how bow-shadow works. Can you please show me how to add shadow like its done in the picture. below im attaching my html and css file and a screenshot for reference

.skills-display {
    width: 50%;
    /* height: 100px;
    border: 2px solid black; */
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

.skill-progress-bar {
    width: 10rem;
    height: 2rem;
    padding: 10px 10px 20px 10px;
    /* border: 1px solid black; */
    border-radius: 0.8rem;
    background-color: lightgrey;
}

.eighty-percent {
    width: 80%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;

    background-color: orange;
    box-shadow: 1px 0 7px grey;
}

.skill-name span {
    color: white;
    font-size: 1rem;
    margin-left: 10px;
}

.twenty-percent {
    width: 20%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #2857a4;
}

.seventy-percent {
    width: 70%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: #20ebb8;
}

.ninety-percent {
    width: 90%;
    height: 100%;
    border-radius: 20px 0px 0px 20px;
    background-color: rgb(252, 220, 0);
}
            <section id="skills">
                <h1 class="section-heading mb75px">
                    <span>
                        <i
                            class="fa-solid fa-chalkboard-user"
                        ></i>
                    </span>
                    <span>SKILLS</span>
                </h1>
                <div class="skills-display">
                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>HTML</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="twenty-percent">
                            <div class="skill-name">
                                <span>C++</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="seventy-percent">
                            <div class="skill-name">
                                <span>Python</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="ninety-percent">
                            <div class="skill-name">
                                <span>JavaScript</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div
                            class="ninety-percent"
                            style="background-color: #43853d"
                        >
                            <div class="skill-name">
                                <span>NodeJS</span>
                            </div>
                        </div>
                    </div>

                    <div class="skill-progress-bar">
                        <div class="eighty-percent">
                            <div class="skill-name">
                                <span>Express</span>
                            </div>
                        </div>
                    </div>
                </div>
            </section>

REQUIRED

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MINE

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Comments

Comment posted by Ahmad

It would help if you could just post the parts relative to your question. Not every single line of your code

Comment posted by Arnav Thorat

Please make a

Comment posted by Twisam Stark

Edited, Please take a look now

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