Think Python (3rd Edition)

Think Python teaches programming concepts — not just Python syntax — through the lens of “computational thinking,” Allen Downey’s term for breaking a problem down into steps a computer can execute before worrying about how to write them. That framing is why it’s often recommended even to people who’ve never programmed in any language before, not just Python beginners specifically.

Free and open-source, now in its 3rd edition, and a common alternative or companion to CS50P for a book-first rather than video-first learning style.