JSFiddle - React, Tailwind, and code Playground

HTML

<body onload="onLoad()">
    <button id="dateBtn">Click me!</button>
</body>

JavaScript

function onLoad() {
    document.getElementById('dateBtn').onclick = function () {
        var dt = new Date();
        dt.setDate(dt.getDate() + 5);
        alert(dt);
    };
}