JSFiddle - React, Tailwind, and code Playground
HTML
<div class="main">
<div class="block">
<input type="text" name="file0"/>
</div>
</div>
<button></button>
JavaScript
$(document).ready(function(){
var i = 0;
$('button').click(function(){
i++
$('.main').append('<div class="block"><input type="text" name="file'+i+'"></div>')
});
});