I Am Interested In Biology

I wonder how I can really get started researching this vast field of science. What if I am mainly just interested in how the human body functions for now, like the endocrine system, for starters? Should I search under the heading of "anatomy" or "medicine?" What are some good books for beginners, to understand some basic terms? I might need to review what I learned in college. Maybe there are some good YouTubers that break it down really well? Does anyone have any advice?