Biology, psychology and political science: what can I do with them?

Hello community!
I am a student, finishing KS3 under the British system abroad, and will be choosing my GCSEs later this March. For the past 2 or so years I’ve been set on pursuing surgery, and have started looking in at medical schools and faculties. In my interest in surgery, I developed a fascination for psychology and all that comes with, alongside most recently having started attending MUNs (model United Nations conferences).
Before I knew it, I realized Im not so sure about wanting to limit myself to surgery, knowing straying from the path of medical school is not a decision to take lightly, and that it takes years before you can start a serious, independent job. It seems to me these 3 majors go hand in hand to confuse students, and since I’ve seen several similar inquires, I was hoping to find some guidance from those who have once had the exact same doubts.

All I am searching for is a bit of insight on my career (study options at least) options and what exactly I could study as I go to university, that might involve at least 2 of the subjects above. (Lastly, maybe it would help to know I plan on taking triple sciences, art, history, business/economics, and a language for my GCSEs.)

Public health policy seems like a natural fit, but most MPH programs don’t require a specific bachelors degree. This degree is sometimes undertaken by medical professionals after working for a few years.

Agree with @VickiSoCal: public health policy pulls all of those elements together. She is also right that they welcome a variety of backgrounds. For example, if you decide that you want to go more social sciences, you can look at an MPH in Social and Behavioral Sciences, whereas if you really like the lab sciences more, you can go the MPH in Epidemiology route (examples only- there are a lot of options).

In what country will you be attending university? that makes a difference in what courses you can consider.