iOS is pretty unintuitive. There’s lots of hidden gestures you have to memorize to get around. I missed androids back button since it always worked, whereas in iOS every app implements it differently. Is there an X in the upper right? A Close in the upper left? Do I swipe down? Swipe left? Etc. even apples built in apps are not consistent.

Proton is designed for games. Have you tried just using regular wine? I bet if you google “wine photoshop linux tutorial” tons of them will pop up