Learning about what makes the human body tick can be a lifelong occupation. The dovetailing subjects of biochemistry, physiology, genetics, pharmacology, and so on are almost inexhaustible - there is always something left to learn, and new discoveries are being made constantly.
Someone studying in this field may become a generalist and often a valuable employee in a hospital, laboratory, or healthcare company. Others, once they've learned the basics, become specialists. Conducting research full-time is one possibility, treating patients directly is another.
One advantage of choosing biomedicine as your first step on your road to a career in health sciences is that you'll be exposed to how various facets of medicine work in the real world. This will often help you uncover your hidden talents and passions, aids in developing cross-disciplinary thinking, and encourages effective communication with your future colleagues.
This is a very competitive sector. Being smart at scientific studies is generally not enough to succeed: the best opportunities often go to the most diligent, motivated students.