JSFiddle - React, Tailwind, and code Playground

HTML

<form id="myform" onsubmit="return addUser()">
    <h2>Add a User:</h2>
    <input id="username" type="text" name="username" placeholder="name"/>
        <input id="email" type="email" name="email" placeholder="email"/>
    <button type="submit">add user</button>
</form>
        
<h2>UsersList:</h2>
<ul id="users"></ul>

JavaScript

var list = document.getElementById('users');

function addUser(){
    var username = document.getElementById('username').value;
    var email = document.getElementById('email').value;
    var entry = document.createElement('li');
    entry.appendChild(document.createTextNode(username + ' ' + email));
    list.appendChild(entry);
    
    return false;
}