JSFiddle - React, Tailwind, and code Playground
HTML
<input type="text" id="focusText"></input>
<button id="focusButton">Set Focus</button>
JavaScript
document.getElementById("focusButton").onclick = function() {
var inputElement = document.getElementById("focusText");
var text = inputElement.value;
inputElement.value=text;
inputElement.focus()
}