Solution 1 :

const myInput = document.querySelector(".myInput");
const myTextarea = document.querySelector(".myTextarea");

myInput.value = "I'm an input value";
myTextarea.innerHTML = "I'm an textarea innerHTML";
<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
</head>
<body>
  <input type="text" class="myInput">
  <textarea cols="20" rows="5" class="myTextarea"></textarea>
</body>
</html>

Problem :

Well, I have a program which uses a speechRecognition plugin from Ionic which takes listen and the result is put in an alert, it would be possible to put the resulting information in an input or a textarea, this is my code

import { Component } from '@angular/core';
import { SpeechRecognition } from '@ionic-native/speech-recognition/ngx'

@Component({
  selector: 'app-voicetext',
  templateUrl: './voicetext.page.html',
  styleUrls: ['./voicetext.page.scss'],
})

export class VoicetextPage {
  
  constructor( private speechRecognition: SpeechRecognition) {}
  
  startListening() {
    this.speechRecognition.startListening().subscribe((speeches)=>{
      alert(speeches[0]);
    },(err)=>{
      alert(JSON.stringify(err));
    })
  }

}

Este es mi HTML

<ion-header
    <ion-title color="light">Voz a Texto</ion-title>
</ion-header>

<ion-content>

  <ion-button 
  (click)="startListening()">
  </ion-button>

 <ion-card class="ion-padding-horizontal">

  <ion-textarea 
  rows="15" cols="20" 
  ></ion-textarea> 

</ion-card>

</ion-content>

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