> *Should I choose Gnome or KDE for a desktop environment?

I suggest people try Gnome first and see how it meshes with you. Learn a few common keyboard shortcuts, especially Super Key, Super + (type to search), Alt+tab, etc.

If you know you're a customizer/tinkerer then maybe start with KDE. The knobs can be overwhelming though for people who want a more "just works" kind of experience.

Regardless, Fedora is IMHO the best experience (for a usable general purpose system) for both, so that's a great place to start.