Switching to Linux from windows

I really don't want to use windows 11 anymore so I've thought to install ubuntu.

The plan is to install it on another bigger and faster drive and get rid of windows that's still knstalled on an older one. I'm just asking for help and advice and if I need to make backups or how to keep the files and photos on C: safe while deleting windows.

I kind of have no idea what I'm doing.