Its paid and not FOSS but you can use it without paying but some QOL features are missing. boot.dev . Its full backend course btw. There are 2 git course. Basic and advanced.

I am glad i am not living in that timeline.

Yet

If you want that sweet dopamine hit of solving problem with out the overhead of doing a project just try leet code. Like that Chinese ping pong player. Nothing wrong with that if you are not gonna pursue it as a job. Ps. You can use different language then you are familiar with like Haskell or ocamel. It can really help you think differently and look problems in new light.

Just to add my two pennies

It’s to add my two penis, if you are a snake and a male.