Upload multiple files with preview and input fields

I try to create a Uploadform with 2 Functions:

1. preview images before upload | Done by this Thread: Adding multiple images with preview
2. Show multiple input fields for each upload file. and send them in req.files

i have no clue how to archive this 🙁

   $(document).ready(function () {
                        $('.uploadSubmit').on('click', function () {
                            var selected = [];
                            $('.dt-checkboxes:checked').each(function (t, d) {
                                selected.push(d.parentElement.nextElementSibling.nextElementSibling.innerHTML);
                            });
                            $('#mailgroupIDS').val(selected);

                        });

                        let imagesPreview = function (input, placeToInsertImagePreview) {
                            if (input.files) {
                                let filesAmount = input.files.length;
                                for (i = 0; i < filesAmount; i++) {
                                    let reader = new FileReader();
                                    reader.onload = function (event) { 
                                        $($.parseHTML("<img>")).attr("src", event.target.result).appendTo(placeToInsertImagePreview);
                                    };
                                    reader.readAsDataURL(input.files[i]);
                                }
                            }
                        };
                        $("#_uploadFiles").on("change", function () {
                            $("div.preview-images").html("");
                            imagesPreview(this, "div.preview-images");
                        });
                    });