JSFiddle - React, Tailwind, and code Playground

HTML

<div id="buttonscontainer">
    <button class="button" id="add" onClick="addRect();">add</button>   
    <button class="button" id="remove" onClick="removeRect();">remove</button>    
</div>

<main id="main">
    <div class="rect"
    <p> kapil singh Negi </p>
    <p> kapil singh Negi </p>
    <p> kapil singh Negi </p>
    <p> kapil singh Negi </p>
    </div>
    <div class="rect">ble</div>
</main>

JavaScript

function addRect(){
     document.getElementById("main").innerHTML += '<div class="rect"><p>kapil singh Negi</p><p> kapil singh Negi</p><p>kapil singh Negi</p><p>kapil singh Negi</p></div>';
 }

 function removeRect(){
     var main = document.getElementById("main");

     if (main.children.length > 0) {           
         main.lastChild.remove();                                                            }
 }