Get the basics and pre req's out of the way first...there are classes your school may require you to take regardless of your major. When I was taking bio classes for my major, I also took 1 other class a semester not related to anything to do with Bio just to see what else was out there and how I handled the material. I tried something form a handful of different fields until I landed on something I really liked. Still finished with a bio degree but wound up taking enough writing and lit classes for a minor. Those other classes I took helped me in my working career more than the bio classes did. Use the time to find out what you are into, passionate about, and can succeed in.