JSFiddle - React, Tailwind, and code Playground

HTML

<p>In next example we can add new child element to this list:</p>
<ol id="list">
    <li>1</li>
    <li>2</li>
    <li>3</li>
</ol>
<button onclick="addNewElement('li', 'list')">Add new li-element to this list</button>
<p>In next example we can add new child element to this div:</p>
<div id="someThing">Something here</div>
<button onclick="addNewElement('div', 'someThing')">Add new div-element to this div</button>

CSS

div {
    border: 2px solid #eeeeee;
    background-color: #dff0d8;
}
ol {
    background-color: #dff0d8;
}
li {
    background-color: #eff0c8;
}

JavaScript

function addNewElement(elementType, parentId) {
		let parentElement = document.getElementById(parentId);
    let newElement = document.createElement(elementType);
    
    newElement.innerHTML = 'new element';
    parentElement.appendChild(newElement);
}

window.addNewElement = addNewElement;