You have to link the anchor to a heading, as far as I know. One workaround to link to a plot would be to add an empty heading below it.

Create an anchor next to an empty heading below the plot, like this:

# {#YourAnchorNextToTheHeading}.

Wrap the word/sentence you want the link into in square brackets [], followed by your anchor wrapped around round brackets.

Here is an example:

# page 1
R code that was used to perform the regression analysis can be found by clicking [HERE](#page2).



pagebreak

# page 2

```{r echo = FALSE}
plot(cars)

```

# {#page2}

EDIT: Adding color to the linked text:

I found this on the the R Cookbook tutorial::

Create a R function to write raw HTML or LaTeX code:

```{r echo=FALSE, include=FALSE}
colorize <- function(x, color) {
  if (knitr::is_latex_output()) {
    sprintf("\textcolor{%s}{%s}", color, x)
  } else if (knitr::is_html_output()) {
    sprintf("<span style='color: %s;'>%s</span>", color, 
      x)
  } else x
}

```

Then add it to the text (make sure to wrap r colorize("HERE", "blue") with back ticks (`))

page 1

R code that was used to perform the regression analysis can be found by clicking r colorize("HERE", "blue").

Let’s say I have an R markdown pdf document that have 2 pages.

# page 1
R code that was used to perform the regression analysis can be found by clicking HERE.

What I want is when I click on “HERE” it refers/takes me to the code in the page two. Suppose the page 2 contains the following code.

# page 2
model = lm(y~x, data = data)

Any ideas?