How did lawyers know they actually wanted to be lawyers and I’d taking the right carrier path.
I had a career before becoming a lawyer. I saw lawyers in action professionally and decided that I might be good at that, and that I might really be able to contribute. Thus, I ended up going to law school several years after I graduated from college (not directly from my undergraduate degree). Frankly, it allowed me time to make sure law school was really something I wanted, and the time in my first career put me in a better place financially to afford law school (even with scholarships, it still cost a lot!).
So, with all that said, the law is actually my second career path. Even within the law, I went from a big law firm to an in-house legal position within a company. And within my practice, I've started with environmental law and transitioned to anti-corruption law. Once you've become a lawyer, your career path will still continue to unfold!
It is really hard to know the future, so my advice is research the law and what you will need to become a lawyer, then make a plan (& budget, alas all the education required to become a lawyer does cost money). But check in with yourself periodically to ensure you are still comfortable with that plan. And give yourself permission to change the plan, and follow a new path if a different field takes your interest. (The world needs chemists and engineers and architects and nurses and so many other professionals, too!) A lot can change between high school and university, and then between university and law school, and even after law school! Lots of lawyers end up in business or political positions where they do not act as lawyers, but where they rely on the skills they learned in law school and when they practiced law. I honestly do not think there is one "right" career path for you - or any student - because there are so many variables ahead in your life; however, that you can map out what it takes to follow certain professional goals, revisit that road map and make adjustments as needed.
Good luck - in the law or whatever field you end up !