Laravel-7: Edit Image via modal and ajax - ajax

Question

So I'm done with trying to upload image using modal and ajax, now I want to edit it. So my modal trigger is the uploaded picture itself. My problem is how do I get the data from the database and display it on my modal? Am also having this error:
Uncaught ReferenceError: data is not defined
MODAL TRIGGER: (user/gallery.blade.php)
#foreach($galleries as $art)
<div class="card" style="width: 20rem;">
<img class="card-img-top" src="/storage/upload/{{$art->upload}}" alt="Card image cap" id="editUpload" data_id="{{$art->id}}">
</div>
#endforeach
MODAL: (scripts/editUploadModal.blade.php)
<div class="modal .modal-lg bg-white" tabindex="-1" id="editUploadModal">
<div class="container">
<h3 class="text-center">EDIT UPLOAD</h3>
<form id="editForm" enctype='multipart/form-data'>
<div class="modal-body">
<input type="text" name="id" id="editId">
<input type="file" name="upload" id="editUpload"><br>
<img class="card-img-top" src="#" id="imageResult"><br>
<label>CAPTION</label>
<input type="textarea" class="form-control bg-white border-dark" name="description" id="description">
</div>
<button class="btn btn-danger">DELETE UPLOAD</button>
<button class="btn btn-success">SAVE</button>
</form>
</div>
</div>
SCRIPT: (scripts/editUpload_script.blade.php)
<script>
$(document).ready(function(){
$.ajaxSetup({
headers: {
'X-CSRF-TOKEN': $('meta[name="csrf-token"]').attr('content')
}
});
$('body').on('click','#editUpload', function(){
$('#editUploadModal').modal('show');
console.log($(this).attr('data_id')); //DISPLAYS ID
data_id = $(this).attr('data_id');
//THIS IS WERE AM STUCK FROM BECAUSE IT IS NOT DISPLAYING THE DATA IN CONSOLE
$.get("{{route('gallery.index')}}" + '/' + data_id + '/edit', function(Data){
console.log(data.upload + " " + data.description)
$('#editId').val(data.id);
$('#editUpload').val(data.upload);
$('#description').val(data.description);
//display image
reader.onload = function () {
$('#imageResult').attr("/storage/upload/" + data.upload);
});
});
});
</script>
CONTROLLER: (GalleryController.php) btw, I added use Response;
public function edit(Gallery $gallery)
{
return Response::json($gallery);
}