Hello Questions68,
If you are interested in a specific photo, you can see what device it was taken on! If you tap on the i icon or swipe up on any photo it will show the metadata. In simplest terms, just think of metadata as information about the photo, this includes the timestamp, photo/video name, what device it was taken on, what lens was used, etc.

I took this video last week! You can see it tells me it was taken on Apple iPhone 14 Pro Max, which is the current iPhone I use.
Alternatively,
- Open Photos
- Tap Search
- In the search bar, type the device!

This should group all the photos taken on a specific device. It will also group photos you didn't take but are within the Photos app. For example, I've never owned an iPhone 12 Pro Max, but I have pictures saved from a family/friend who does.
I hope this helps!