Welcome to your GNU/Linux jounery.

Before you distro hop again, take your time exploring the os and terminal it will make installing the real arch linux easier.

I want to focus mainly on grey hat stuff. Based on that which hacking category should I choose and where can I find resource to learn them?

Where can I learn those things?

There is no such thing called umami.

You can also use wine and other emulators to play games.

I always keep an old windows iso file just incase I need to use it.