The best way to learn is to build something for someone else. When someone else sets the requirements you have to engage in real problem solving and research the best tech to solve the problem. This keeps you from following just the easiest path as well as exposes you too new ideas.
You can do this at work, for a local non profit, for your friend's weird startup idea, ...
That's one way to learn time schedules, efficiency, but not necessarily the rest of a programmer skillset
I had the most prolific time of my life, when out of work for 6 months, and I did completely random projects, a 2048 solver (it was trendy at that time), a connect-four adversary and many others ideas https://caub.github.io/misc/, just imagination, learning the algorithms, also some leetcode for future interviews, still then this moment helped a lot building myself
11235813213455|2 years ago
I had the most prolific time of my life, when out of work for 6 months, and I did completely random projects, a 2048 solver (it was trendy at that time), a connect-four adversary and many others ideas https://caub.github.io/misc/, just imagination, learning the algorithms, also some leetcode for future interviews, still then this moment helped a lot building myself