JSFiddle - React, Tailwind, and code Playground
HTML
<button>add input</button>
<br>
<form action='blabla.php' method='post'>
<input type='text' name='desc_1'>
</form>
JavaScript
$("button").click(function(){
var count = $("input").length + 1;
$("form").prepend("<input type='text' value='desc_" + count + "' name='desc_" + count + "'><br>");
});