JSFiddle - React, Tailwind, and code Playground

HTML

<div class="des">
    <h1>Test</h1>
        <div class="desleft">
          <p>Lorem Ipsum.</p>
        </div>
        <div class="Right">
           <button>Test</button>
        </div>
</div>

JavaScript

alert(document.getElementsByClassName("desleft")[0].previousSibling.previousSibling.tagName)