JSFiddle - React, Tailwind, and code Playground

HTML

<iframe id='the_iframe'></iframe>

JavaScript

var urls = [
    'https://www.youtube.com/embed/wZNYDzNGB-Q',
    'https://www.youtube.com/embed/DRs0Kw2rUVQ',
    'https://www.youtube.com/embed/JmENgrVOwgA',
    'https://www.youtube.com/embed/2vEStDd6HVY'
];
var seconds = 2;
function openNext(){
    document.getElementById('the_iframe').src = urls.shift();
    if(urls.length)setTimeout('openNext()',seconds*1000);
}
openNext();