Question

If you create a database with a media & files property and store multiple images in one entry of this database, can you show these images in a gallery ?

Answer 1

There is no option to show a gallery from a single Notion property.

If you create a Gallery view of your database, it will show only one of the images when you select Card preview: files. So you can have a Gallery view for all your entries displaying one of the images, but not all of them.