JSFiddle - React, Tailwind, and code Playground

HTML

<h1 id="TXT">MUDE O TEXTO</h1>

<input type="text" id="INPUT01" width="100%" />
<br/>
<input type="button" onclick="setTexto('TXT')" value="MUDAR O TEXTO" />

CSS

body {
    font-family:'segoe ui';
}

JavaScript

function setTexto(id) {
    var tx = document.getElementById('INPUT01').value;
    document.getElementById(id).innerText = tx;
}