Very much similar experience to yourself, when I was learning from YouTube tutorials I refused to copy/paste from their repos and instead typed everything out. Maybe changing variable names or structure.

I can definitely say it helped me learn a lot more than just blindly copy/pasting everything over.

> When I was learning to code at college, by myself (I did a Business degree), I bought a book on iOS development[0]. This book mandated that you type all the examples out line-by-line. I thought the idea was a pretty silly one, but I stuck with it because I didn't know what I was doing and wanted to learn.

It seems like an exercise to force you to attend to the details. I had a similar experience with a "certified X programmer" exam my employer bought for me. I wouldn't say passing such an exam makes anyone a good programmer, but it was an unexpectedly valuable experience because it forced me to attend to a broad set of details (instead of getting a spotty command of them, due to path-dependent experience).

Similar thing happens with notes: I rarely reference them but taking them keeps my mind from wandering.

I like coding katas (or even trying leetcode problems) when learning new languages.