Best place to learn Python 3.X and get an idea of API usage in Python?

I actually learn a language just by having a idea of what I could do (like building a simple web server with python and django) and then I just jump into it, do dozens of research (so, django tutorial, python docs, django docs and so on)

I think the best way to learn programming is to programm.
Just reading the docs alone, or just typing without reading won't bring you forward

Other ideas if you want some: music player, mp3/flac tag editor, client server Chatrooms (native python or implement this in Django with web sockets)

And for api usage, have a look at the requests package
It makes it really easy to do something like starting a session, login to online service (for example your universitys [don't know English word for it: Vertretungsplan (when teachers are ill) ] and then use this session to get the Infos from the website (basic js knowledge needed to understand the login process in a js webapp and use the network inspector to see where the data comes from.

In Germany most schools/universities use DaVinci as system for student management and so on. If they have a service, then you should be able to see where the data comes from, fetch it, parse it and then send you a notification on update via telegram bots