I’m reading books, what order should i go in?
Python is OS agnostic really. You can install, run, edit Python on Windows, Mac, Linux and it doesn't really matter.
I do quite a bit of develop from my Windows box and some testing and then move to my target system for live testing and the target in my case tends to be Linux or BSD.
Learning Linux is not necessary for Python. However understanding the target OS is important when you are trying to debug issues and work with module dependencies!
I just signed up for a beginner course for both, you think a raspberry pi will be suffIcient? Thank you
Can I dev on my iPad Pro? If not, I’ll buy a Mac air?
For most needs, yes.
Sure. rPi is a common target of mine too.
Can you? Likely as all you really need is a text editor. However having a nice keyboard makes the experience nicer. I don't know if you can install Python on the iPad either which would make it easier for learning to have the Interpreter and a nice IDE with syntax highlighting and "suggestions".