I started college at 17 and was (supposed to be) restricted to the all female dorm. It turned out they put me in a co-ed dorm (single sex on each floor).
My daughter started at 17 and there were some forms I had to sign. IIRC, anything medical, and anything NCAA related (drug testing and releasing those results), some travel forms.
It wasn’t a big deal. I signed a ton of forms anyway, so what was 4-5 more?
There were a few scholarship programs my daughter couldn’t apply for because she wasn’t 18. They were government programs. There were also government internships she wouldn’t have been allowed to take because she would have had to be 18, but most of those were for the summer following freshman year and by then she was 18.