Sandisk iXpand flash drive. How to check backup file structure.

Just bought one and downloaded the app and it seems to have backed up ok. However I would like to check the flash drive to see if ALL the photos and files on my iPad have been backed up. At this time I have no knowledge of how to check the files folder without the image gallery opening up, to confirm they are all there. In short how do I see all the backup content in file order? Is it possible? I am running Mac Monterey.