Intimidated by college! Unique scenario...

I feel that high school hasn't properly prepared to me. I NEVER have homework, MAYBE an hour a week tops. Yeah, I have a 4.3 GPA, but I feel like it was handed to me since I never had homework and never had to really study for my high school courses. I feel that this is all especially frustrating since I'm majoring in biology and need a 3.5+ GPA in college to go to dental school. When I first took my ACT with no prep, I scored a 21. Plain average, 50 percentile score. I had to study for months...

Intimidated by college! Unique scenario...