I for one would love to hear more about your transition as someone who’s been with Python for a while now but struggling to make Swift stick (last attempt was with SwiftUI, which is awesome but very young).
I didn't do anything that special to learn it. I gave the The Swift Programming Language book (1) a read and then started to get my hands dirty, using Google when needed. I had done some iOS development a long time ago, which also helped. I almost immediately found it just as easy to write as Python (and in some respects easier) but with a stronger type system. It also has a lot of great tooling like Playgrounds. So I guess my advice would be to give yourself a project which you want to use Swift for, ideally where you have no other alternatives. I've also tinkered around with using Vapor to create web servers using Swift, so that might be another option.