JSFiddle - React, Tailwind, and code Playground
HTML
<div class="DOMParent" style="width: 100%; border: 1px solid #ff0000; margin: 10px; padding:10px;">
<div class="title">
<div class="titleText">Category 1</div>
<button class="btn">id="btn" Click Me</button>
</div>
</div>
<div class="DOMParent" style="width: 100%; border: 1px solid #ff0000; margin: 10px; padding:10px;">
<div class="title">
<div class="titleText">Category 2</div>
<button class="btn">id="btn" Click Me</button>
</div>
</div>
JavaScript
$(".btn").click(function(){
console.log($(this).parent().find(".titleText"));
$(this).parent().find(".titleText").text("This is the new TITLE Text");
});