JSFiddle - React, Tailwind, and code Playground

HTML

<button id='btn'>Click me</button> 
    
    <div class="field">
        <label>remarks:</label>
        <textarea id="id_remarks" name="remarks"></textarea>
 </div>

JavaScript

document.getElementById('btn').onclick = function (){
    if (document.getElementById('id_remarks').value =="")
    {
        alert("is Empty");
        return;
    }
    
 
 }