JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-3.1.1.min.js"></script>
<input id="num-duplication" type="number" min="0">
<button id="btn-dupliquer">Duppliquer</button>

<div id="toDuplicate">
  <div class="mon-div">mon div</div>
</div>

<div class="result"></div>

JavaScript

$(function() {
	$('#btn-dupliquer').on('click', function() {
  	var numDuplication = $('#num-duplication').val();
    
    if (numDuplication > 0) {
    	var div = $('#toDuplicate .mon-div');
      $('.result').html('');
    	for (var i = 0; i < numDuplication; i++) {
      	$('.result').append(div.clone());
      }
    }
  });
});