JSFiddle - React, Tailwind, and code Playground

HTML

Product ID: 1065

    <input type="text" class="text cart_qty" id="Form_OrderForm_Product-1065-qty" name="Product[1065][qty]" value="1" />

    <input type="text" class="text prod_id" id="Form_OrderForm_prod_1065" name="prod_1065" value="1000" />

    <input class="hidden" type="hidden" id="Form_OrderForm_hidden_1065" name="hidden_1065" value="1.45" />

    Line total: <span id='Product_1065_Line' class='cart_price_line'>1.45</span>

<hr />

    Product ID: 1337

    <input type="text" class="text cart_qty" id="Form_OrderForm_Product-1337-qty" name="Product[1337][qty]" value="1" />

    <input type="text" class="text prod_id" id="Form_OrderForm_prod_1337" name="prod_1337" value="500" />

    <input class="hidden" type="hidden" id="Form_OrderForm_hidden_1337" name="hidden_1337" value="1.45" />

    Line total: <span id='Product_1337_Line' class='cart_price_line'>1.45</span>

<hr />
Total: <span id="total_price_curr"></span>

JavaScript

$("document").ready(function() {

    $('input.cart_qty').keyup(function(){
        var total = 0;
    
        $('input.cart_qty').each(function(index) {
            var product_id = $(this).attr("id").split("-")[1];
            
            var quantity = $(this).val();
            var price = $("#Form_OrderForm_hidden_" + product_id).val();
        
            var line_total =  price * quantity;
            total += line_total;

            $("#Product_" + product_id + "_Line").html(line_total);
        });
        
        $("#total_price_curr").html(total);
        $("#Form_OrderForm_totalHidden").val(total);
    
    });

});