JSFiddle - React, Tailwind, and code Playground

HTML

<input onclick="txt()" type="number" min="0" max="3" size="4" value="0" id="iptnbr">



<textarea id="txt1" class="txt"></textarea>
<textarea id="txt2" class="txt"></textarea>
<textarea id="txt3" class="txt"></textarea>

CSS

.txt {display:none;}

JavaScript

function txt() {
var qteValue = document.querySelector('#iptnbr').value;
      if(qteValue == 1)
      {
      document.getElementById("txt1").style.display="block";
      }
      else if (qteValue == 2)
      {
      document.getElementById("txt1").style.display="block";
      document.getElementById("txt2").style.display="block";
      }
      else 
      {
      document.getElementById("txt1").style.display="block";
      document.getElementById("txt2").style.display="block";
      document.getElementById("txt3").style.display="block";
      }
}