Think Python is pretty good.
https://greenteapress.com/wp/think-python-2e/
There's also a good chance you'll find it easiest to learn by starting with the bare minimum to make a functional program (which is quite little), and looking things up as you go along. Find some useful task to automate, and automate it. Start small. Work your way up.
Definitely use the official documentation:
https://docs.python.org/3/
And most of all, write a lot of code as you're learning, don't just read.
The REPL is your friend, and you should use it a lot. Its built-in help function is also useful.