Nikko chan, i will give you advice that I was given many years ago - just start. Go on the Uni website first, make an appointment with a course advisor, and start - take one class or three but just start.
I started college in my 20s, got thisclose to finish, and didn't. When i was 44, newly separated from now-ex H, working full time and raising a child i went back to school (in fact, it was one of the first things i did after our separation). It's not easy, there is often information online that doesn't make sense to anyone but the registrars at the uni, but once you get started it starts to get clear. Or at least clear-ER. when i started, i sounded a bit like you - very unsure, i think i sorta kinda knew what i wanted to study, but i was focusing on the difficulties and the obstacles. A friend told me "just go and register for one course". and I did - i actually took two courses that were the basic prerequisites and went hand-in-hand. and i was hooked. and i actually ended up with a different major ( i was able to switch my major and minor without losing any courses) which happens a lot. so what i'm saying is - right now you don't know what's going to be, what you want, what you may want in the future, but just start and take a course or two and see what happens.