This is a perfect valid approach though ! My first few years in self-hosting I learned soooo many things: CLI, Shell, scripting, networking, containers...

Doing my own AV1 encodes I learned alot about audio/video processing, metadata, ffmpeg, av1an....

Maybe not as structured as OP asked for, but there's way to much to learn in the OS world that a whole life is not sufficient to have it all ! However, following that said goal, you will learn alot arround other stuff and improve overall.

If your goal is to learn the Linux system and all the nitty gritty arround it, good luck :/ it takes more than 1 person to make an OS work, so understanding all the bells and whistle is just crazy IMO !