Ideally, you'll want to find which methodology (or -ies ideally) works best for you, and continue to branch from there.
The idea of 'how do you learn' extends above answers like 'books' or 'youtube' or 'coursera', and fits better in the categorization of 'I like to Listen', 'I like to try', 'I like to watch'.
Ideally, find which of these, or which combination of these is most interesting to you, and then find the appropriate tool to leverage that.
Personally, I like to Read, and I like to Do.
I have a brainstorming meeting with my Team once every 2 months where we spitball home project ideas, and have a show and tell from work we've done in our spare time. Once I've settled on an idea, I apply the above concepts to learn as much as I can about it.
For example, the last project was to build and solve a Rubiks cube. I read about the mathematics of a Rubiks cube, and built models alongside. I know that having reference material, and an instance of CLion open next to me is my recipe for successful learning.