This totally depends upon you interest.
If you are in PCM then you can go for engineering and if interested in PCB then  you can go for doctor studies.

Talking about maths, it is essential to befriend it if you aim to crack some highly competitive exams like JEE and NEET. Also, if your maths concepts are clear, scoring in it is way easier than Biology.
If you are thinking about Biology, you definitely need to be inclined towards medical field and related research. Without these it's really hard to survive Biology because it requires massive memorization ability and focus and relatively more time per day than maths.

I hope you understand there is a difference between your interest and career. As both have different directions you ought to choose out of the 2.

Good luck.