What is the best way to study for biology?

I am taking an Honors Biology course as a freshman in high school, and I am looking for some ways to strongly improve my performance in this course. I am considering a career in medicine when I get older.

I took high school biology and AP Biology. High school biology, such as your Honors Biology class, is probably going to be best mastered via memorization of terminology and a surface-level understanding of processes. If you decide to take biology again in high school at an advanced level, like AP, IB, or dual enrollment, you will need strong conceptual knowledge (explanations for biological processes and how they function/interact, for example) which can get pretty technical on top of terminology.