JSFiddle - React, Tailwind, and code Playground

HTML

<form action="pag.php" method="post">
 <table id="InputsWrapper">
<tr>
    <th><b>&nbsp;&times;&nbsp;</b></th>
    <th><b>PIATTO</b></th>
    <th><b>PORTATA</b></th>
    <th><b>QUANTIT&Agrave;</b></th>
</tr>
 </table>

 <div class="centra">
    &nbsp;
    <a href="#" id="AddMoreFileBox">
        <input type="button" value="Add">
    </a>
    &nbsp;<hr>&nbsp;
    <input type="submit" name="submit" value="Create!">
    &nbsp;<hr>&nbsp;<br>
</div>
</form>

JavaScript

$(document).ready(function() {

var InputsWrapper   = $("#InputsWrapper"); //Input boxes wrapper ID
var AddButton       = $("#AddMoreFileBox"); //Add button ID

var x = InputsWrapper.length; //initlal text box count
var FieldCount=1; //to keep track of text box added

$(AddButton).click(function (e)  //on add input button click
{

            FieldCount++; //text box added increment
            //add input box
            var menu = '<td><select name="dynfields[]"><option value="prova">prova</option><option value="tortellini">tortellini</option><option disabled>SECONDI</option><option value="aaaaaa">aaaaa</option><option value="bbbbbbb">bbbbb</option><option value="ccccccc">cccccc</option></select></td>';
            var numPortata = '<td><button class="minus" field="portata\'+x+\'">-</button><input id="portata\'+x+\'" type="number" name="numPortata[]" value="1" size="10" min="1" max="10" step="1" required><button class="plus" field="portata\'+x+\'">+</button></td>';
            var quantita = '<td><input type="number" name="howmuch[]" value="1" size="10" min="1" max="30" step="1" required></td>';
            $(InputsWrapper).append('<tr><td><a href="#" class="removeclass"><b>&nbsp;&times;&nbsp;</b></a></td>'+ menu + numPortata + quantita +'</tr>');
            x++; //text box increment
return false;
});

$("body").on("click",".removeclass", function(e){ //user click on remove text
        if( x > 1 ) {
                $(this).closest('tr').remove(); //remove text box
                x--; //decrement textbox
        }
return false;
}) 

});

$(document).ready(function() {

    // This button will increment the value
    $('.plus').click(function(e){
        // Stop acting like a button
        e.preventDefault();
        // Get the field name
        fieldName = $(this).attr('field');
        // Get its current value
        var currentVal = parseInt($('input[id='+fieldName+']').val());
        // If is not undefined
        if (!isNaN(currentVal)) {
           ...