What I personally do for this is I go by what I call chaotic learning. Spending chunks of my time in different things based whatever interest me at that moment. For example, I am currently only trying to gain expertise in software engineering. I am super interested in math, philosophy, history, science etc too. But currently, I want to focus specifically on software and then after a certain point (idk when that point will be, maybe after I've financial freedom, maybe not), I will explore other fields too. But in software itself, there are so many things to do and learn too. So what I do is, today I am working on a side project to do with the terminal. After a few days, once I publish a v0.1, I will work a bit on an open source project I'm interested in. Post that, I might do some DSA. Post that, maybe back to my side project adding another new feature. Then maybe read one of the many books I want to read. Then maybe try to learn and build my own language and so on. You learn/build different things from time to time, based on what you really want to pick. That works the best for me. Chaos.