JSFiddle - React, Tailwind, and code Playground

HTML

<form action="form_sent.php" method="post">
	<input name="name" type="text" placeholder="Name"><br>
   <input name="phone" type="text" placeholder="Phone"><br>
   <input name="email" type="text" placeholder="E-Mail"><br><br>
   <button>Add more fields</button><br><br>
   <input type="submit">   
</form>