JSFiddle - React, Tailwind, and code Playground

HTML

<input type="hidden" class="code" data-barcode="567" data-total_quantity="3" name="product1" value="Nokia rita" id="product-10105">
<input type="hidden" class="code" data-barcode="567" data-total_quantity="3" name="product1" value="Nokia rita" id="product-10106">
<input type="hidden" class="code" data-barcode="567" data-total_quantity="3" name="product1" value="Nokia rita" id="product-10107">
<input type="hidden" class="code" data-barcode="200" data-total_quantity="3" name="product1" value="book" class="product-200">

JavaScript

$(function () {
        var barcode = 567; // set to whatever you want to search for...
        var sumOfVals = 0;
        $("input.code[data-barcode='" + barcode + "']").each(function () {
            sumOfVals = sumOfVals + parseInt($(this).data('total_quantity'), 10);
        });
        alert("Length: " + $("input.code[data-barcode='" + barcode + "']").length);
        alert("Sum: " + sumOfVals);
    });