How to display a graphic loader when autoloading content?

Question

AJAX

Hello, there is a script that, when scrolling down, loads data on ajax. Can you please tell me how to display the loader in gif or svg format that would be displayed when loading data?
thanks for the help

$(function() {
    var load_more = false;

    $(window).scroll(function() {
        if($("#ajax_next_page").length && !load_more) {
            var url = $("#ajax_next_page").attr("href");
            var offset_button = $("#ajax_next_page").offset();
            if($(this).scrollTop() >= offset_button.top - $(window).height()) {
                load_more = true;
                $.ajax({
                    url: url,
                    type: "POST",
                    data: {IS_AJAX: 'Y'},
                    success: function(data) {
                        $("#ajax_next_page").after(data);
                        $("#ajax_next_page").remove();
                        load_more = false;
                    }
                });
            }
        }
    });
});