JSFiddle - React, Tailwind, and code Playground

HTML

<div id="output"></div>

JavaScript

var message = "Hello World"

function printChar(i) {
    var output = document.getElementById("output")
    var char = message.charAt(i);
    output.innerHTML = output.innerHTML + char;
    if (i < message.length) {
        window.setTimeout(function() {
            i = i + 1;
            printChar(i);
        }, 1000)
    }
}

printChar(0);