JSFiddle - React, Tailwind, and code Playground

HTML

<textarea id="txtTest"></textarea>

<div id="copy">

</div>

JavaScript

document.getElementById("txtTest")
				.addEventListener('keyup', function(ev) {  
						var txtTestValue = document.getElementById("txtTest").value;
            
            document.getElementById("copy").innerText = txtTestValue;
				}
);