So which one can I use for gaming? Which one can I use for development?
There are differences but they're generally in user-space and not what most newbies think. Things like installers, package management, etc. But "generally speaking" all distros are capable of doing what the others can do. They just do it in different ways.
You've basically got categories.
- The mainstreams: Debian-like, RedHat-like, SuSe, Gentoo, etc.
- The Immutables
- "Specialty": Kali, Raspbian, etc.
There are different philosophies on stability vs. being up-to-date, security, etc. But the same software and drivers are available for all of them "generally speaking".
Edit: I'll add that the biggest mistake most people make is distro-hoping. People will have trouble with something like "getting a printer to work" and just start installing new distros until one works. To learn something you need to spend time with it and fix things
Edit 2: I'll also add that choice of distro matters less for experienced users since you realize that it's mostly just about preference.