JSFiddle - React, Tailwind, and code Playground

HTML

<html>

<head>
	<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
	<title>Your Website</title>
</head>
<body>
    <button id="button">Olá</button>
</body>

</html>

CSS

#button{
  width: 200px;
}

JavaScript

const button = document.querySelector("#button");
button.addEventListener("click", loading);


function loading(e){
  e.target.textContent = "Loading aqui"
  setTimeout(()=>{
    e.target.textContent = "Voltei ao normal"
  }, 2000)
}