Everything depends on the desires and potential that exist within oneself.
As the OP said, we have the same opportunity to be able to advise/give advice to others on things that are worth learning.
STEM courses are also very good and there are many choices that can be taken according to your desires and abilities, but my advice is that the difficult thing to find is your potential, so it is important to explore this first.
Exploring our own potential actually won't be that difficult as long as we have the will and ability to know what we can do with something we have mastered. Because someone can certainly judge themselves in this matter, especially if they have previously taken a course that can direct them to become better in life, even though some people may still not be able to give advice to others. However, that doesn't mean that some people can't see opportunities and use them well for themselves, because everyone will definitely care more about themselves before starting to care about other people in any case.
It is not difficult to be able to explore the potential that exists within ourselves and we can see what we like and can benefit ourselves and if we have found what can make us feel comfortable in doing this then this we can continue so that we become experts in that field and when we have become experts in that field we will be able to easily gain expertise in that field so that we will be able to earn income, because everyone who wants to learn a skill field of course they want it to be easy earn income.