PHP generate multiple form fields - php

Question

I am working on a system to edit/create an online food menu.
On the system that creates/edits the menu I would like the user to be able to enter a new item and price in two form fields and then press 'add another item' in turn this generates another form field. The user can keep pressing 'add another item' or simply submit the form.
Ideally it would keep generating forms fields then when the form is submitted an I handle the POST array and do the DB work.
I'm just not too sure on how I can allow the user to essentially keep adding form fields.
This is system is currently written in PHP.
Hi, Looking into this and my current code, this issue I see is that the form itself is also dynamically generated from database results. Your idea I can see working when I create an entirely new menu, but what if I want to edit a current menu and add a new item to it.
This is the code that generate the current form.
if($menuItems->count()) {
echo '<form class="updateMenu" action="" method="post">';
echo '<table class="gridtable gridtableMenu">';
echo '<tr><th>Item Name</th><th>Item Price</th></tr>';
foreach($menuItems->results() as $item){
echo '<tr>';
echo '<td class="menu-name"><input type="text" name="itemName[]" value="' . $item->item_name . '" required></td>';
echo '<td class="menu-price"><input type="number" step="any" name="itemPrice[]" value="' . $item->item_price . '" required></td>';
echo '<input type="hidden" name="id[]" value="' . $item->id . '">';
echo '</tr>';
}
echo '</table>';
echo '<input type="submit" name="updateMneu" value="Update Menu">';
echo '</form>';
} else {
echo '<div class="error">No items have been added to this menu</div>';
}