JSFiddle - React, Tailwind, and code Playground

HTML

<form action="" id="myForm" method="POST">
    <div class="group">
        <input type="text" name="lol[]" value="1.1"><br>
        <input type="text" name="wow[]" value="1.2"><br>
        <input type="text" name="low[]" value="1.3"><br>
        <input type="text" name="wol[]" value="1.4"><br>
        <input type="checkbox" name="checkbox[]"><br>
        <hr>
    </div>

    <div class="group">
        <input type="text" name="lol[]" value="2.1"><br>
        <input type="text" name="wow[]" value="2.2"><br>
        <input type="text" name="low[]" value="2.3"><br>
        <input type="text" name="wol[]" value="2.4"><br>
        <input type="checkbox" name="checkbox[]"><br>
        <hr>
    </div>

    <input type="submit" name="wowlolwow">
</form>

JavaScript

$('#myForm').submit(function(e) {
    e.preventDefault();

    var fd = new FormData();

    var checkedCheckboxes = $('#myForm .group input[type="checkbox"]:checked');
    console.log(checkedCheckboxes);

    checkedCheckboxes.each(function(i, checkbox) {
        var group = $(checkbox).parent();
        var serializedElements = group.children().serializeArray();
        console.log(serializedElements);
        serializedElements.forEach(function(el) {
            fd.append(el.name, el.value);
        });
    });

    console.log(Array.from(fd.entries()));
});