Use the OS you are most comfortable with. When it comes to programmming try and learn 1 “thing” at a time. If you trying to learn Python and how to use Linux as well as Python then you learning 2 (or more…) things at once so stick with what you know for now. If you are comfortable with Linux (or Mint as you say) then stay with that because I have found running Python on Windows is a Pain but that could just be the environment we are using. Good Luck and Have fun!