JSFiddle - React, Tailwind, and code Playground
HTML
<input id="Text1" type="text" />
<input id="Button1" type="button" value="Click Me" />
<input id="Text2" type="text" />
JavaScript
var myButton;
myButton = document.getElementById("Button1");
myButton.onclick = function () {
var val = document.getElementById("Text1").getAttribute("value");
var val = document.getElementById("Text1").value;
document.getElementById("Text2").setAttribute("value", val);
};