JSFiddle - React, Tailwind, and code Playground

HTML

<button type="button" class="com-yes-btn2 feedback-btn-grey empx11b12" id="btnYes" onclick="javascript:ClickYes();">Click HEre
</button>

<input type="text" id="txtMsg" />

JavaScript

$(document).ready(function(){
$( "#txtMsg" ).focus(function() {
  if($(this).val()=='Tell me more'){
      $(this).val('');
      $(this).css('color','black');
  }
});
$( "#txtMsg" ).blur(function() {
  if(!$(this).val()){
      $(this).val('Tell me more');
      $('#txtMsg').css('color','#CCC');
  }
});
});

 function ClickYes() {      
     // $('#txtMsg').attr('placeholder', 'Tell me more');
      $('#txtMsg').val('Tell me more');
      $('#txtMsg').css('color','#CCC');
    }