Nesting loops and statements in php

i have this code and i want to add checkbox according to fetched number from database with php and when clicked on checkbox update a field in db with jquery, this work for 1 checkbox but this cant work for more checkbox and Also my PHP loop does not work how i can add checkbox with loops and when user click on any checkbox update His own field on database, anybody can resolve my problem ? my jquery code:

        var returnVal = ("Are " + "you sure?");
        if (returnVal) {
            postToServer($(this).prop("checked"));

        } else {
            $(this).prop("checked", !$(this).is(":checked"));
        }
    });
    function postToServer(state) {
        let value = (state) ? 1 : 0;

        $.ajax({
            type: 'POST',
            url: 'checkbox.php',
            data: {'value': +value},
            success: function (response) {
                //handle response
            }
        });
    } 

and my php code:

   $sql1="SELECT * FROM `users` ";
   $result1= mysqli_query($conn,$sql1);
   $row1=mysqli_fetch_assoc($result1);
   $lights=$row1["lights"];
    for ($i=0; $i < $lights; $i++){
        if ($row["value"]=='1'){
echo "<input type=\"checkbox\" class=\"checkbox\" id=\"mycheckbox\" checked=\"checked\">";
    }else {
            echo "<input type=\"checkbox\" class=\"checkbox\" id=\"mycheckbox\" >";
        }
    }