JSFiddle - React, Tailwind, and code Playground

HTML

<div id="pri"></div>

JavaScript

var i = 0;
var delay = 300;

function callMe() {
    //       var i=0;
    console.log("Hello World");
    document.getElementById("pri").innerHTML="Hello World";
    i += 1;
    if (i == 10) {
        i=0;
        delay = 1000;
        console.log("......Pause");
         document.getElementById("pri").innerHTML="......Pause";
    } else {
        delay = 300;
    }
    setTimeout(callMe, delay);
}

window.onload=callMe();