如何自动获取多个表单

Question

I'm doing a HTML form, it's meant to create step to pass on a game and I want to be able to enter a number and when for example I enter 5 it instantly show me 5 form to fill and create new step but when I try it doesn't appear how can I do please?

<h3>Insertion des étape :</h3>

<form action="InsertionEtape.php" method="post">
    <input type="number" name="quantity" min="1" max="5">
    <br>
    <?php for ($i=0; $i < $_GET['quantity']; $i++) {
       ?>
        <h5>Nom de l'étape</h5>
        <input type="text" name="NomEtape" size="40" maxlength="40">
        <br>

        <h5> Description de l'étape </h5>
        <textarea name="DescriptionEtape" rows="8" cols="80"></textarea>
        <br>
        <br>
        <input type="submit" value="Valider">
        <?php
     } ?>
</form>

Answer 1

<h3>Insertion des étape :</h3>
<form action="index.php" method="post">
    <input type="number" name="quantity" id="quantity" min="1" max="5"> 
    <div id="formcontainer">
    </div>
    <input type="submit" value="Valider">
</form>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script>
    jQuery(function($) {
        $("#quantity").bind('keyup mouseup', function () {
            var count = $('#quantity').val();
            var htmlf = '';
            for (i = 0; i < count; i++) {
                htmlf += "<h5>Nom de l'étape</h5><br/>";
                htmlf += '<input type="text" name="NomEtape_"'+i+' size="40" maxlength="40">';
                htmlf += "<h5>Description de l'étape</h5><br/>";
                htmlf += '<textarea name="DescriptionEtape_"'+i+' rows="8" cols="80"></textarea>';
                htmlf += "<br/>"
            }
            $("#formcontainer").html(htmlf);
        });
    });
</script>

Simple Just run the code and you can find yourself easy.