At the age of 26, what's worth spending time studying?

There is a saying that "it is never too old to learn", and this positive attitude is still very correct.

If you are 26 years old and still not confused about your job, you can learn some other skills in your spare time. For example, playing piano, singing, playing guitar, playing Go and so on. It is very helpful for a person's cultivation. It is not impossible to study hard, go deep into it and make a living.

So I think, as long as you find something valuable, you can take the time to learn it, and there is definitely no harm.