JSFiddle - React, Tailwind, and code Playground

HTML

<div id="block1" style="display: none">block1</div>
<div id="block2" style="display: none">block2</div>
<div id="block3" style="display: none">block3</div>

JavaScript

function randomInteger(min, max) {
  var rand = min + Math.random() * (max - min)
  rand = Math.round(rand);
  return rand;
}

document.getElementById("block" + randomInteger(1,3)).style.display = "";