I believe selecting courses in which you love!
In order for you to do well in the IBDP you must study a lot! I know it sounds scary but if you like what you are learning you will succeed. I as well want to go into medicine and sadly my school doesn't offer a wide array of options. If yours does, go for what you want. Going into medicine does not force you to be in a certain group per se. You may come from any undergraduate degree with the medical school pre-requisites and get in. If you love chem (a bunch of math) and bio (memorization is key) do it at hl! If you also like english do it at hl as well (deep understanding)!
Let me know if you have any other questions or concerns!
- Kylie :)