Like someone else said, try MATE, it is more like windows and even though I’m not a windows user, I find it less confusing than gnome.
to some extent though maybe not as bad as before. Solution seems to be buy a Thinkpad since that’s what more devs tend to use. I’ve stayed with that plan and haven’t had much trouble, though at work I had an Acer laptop that also worked fine.
Yes, I generally run Debian, including on small servers where there is not even a window manager (because no screen), much less a browser, music player, or anything like that.
Generally stuff like that requires root, but root just means admin privs. It’s normally protected by a password that you yourself choose when you install the OS. That is, the idea is that you own your computer and can do what you want with it, so of course you have root and can use it when needed. Android is the weird exception that breaks that model, transferring ownership of your phone to app vendors and keeping you out of the application data.
No
DE=desktop environment? Ermmm… maybe not so easy. Simplest might be separate user accounts for different DE’s? Idk, I just use MATE though I’ve played with XMonad n the past.
Wayland = relatively new window system (API through which applications show stuff on the screen), intended to replace X (older system). Docker = container system for wrapping an application and its dependencies in one package, to prevent the Linux version of “DLL hell”. This is mostly used on servers as Linux’s packaging systems tend to be better than Windows’s and not get you into too much trouble, as long as you don’t try to mix approaches on a single machine.