It’s late January, so if you’re a high school senior, then you already sent out your applications, so you’ll have to look at where you get accepted, and what majors you could do at those specific schools. If you are interested in marine biology, look into summer programs at the Woods Hole Oceanographic Institute and the Marine Biological Labs (now affiliated with U Chicago). Also National Fisheries in Woods Hole. But make sure that the program comes with housing or that you have someplace to crash there - housing in the summer is extremely difficult to find.