Aiming for Oxbridge Medicine

Is it worth sticking on 4 A levels? I’m in year 12 and I’m doing math further math bio chem and an EPQ so far my grades are fine but I’m planning on dropping further math in the beginning of year 13. I was just worried going back to 3 might make me less competitive for Cambridge.

No need to worry, Cambridge does not require you to take 4 A-levels for Medicine and it does not make you less competitive for Cambridge. Plus, they look at applications holistically - looking into UCAT, personal statements, interviews, etc…
If you think about it, doing 3 A-levels in the long term may be better as you can focus on getting those 3 A-levels to a higher grade result.

a friend of mine got an oxford med offer this year and he is only doing three. generally med schools aren't bothered by four a levels so you shouldn't worry about that imo. what matters are ucat and interviews so focus on those when the time comes (this would be a good time to start getting familiar with the ucat by doing a few questions from books, but start intensive practice with medify etc. during holidays)

Is he from a state school?

Btw, it doesn't matter where you train as a doctor. All Med degrees are accredited as equal by the GMC and all follow exactly the same syllabus. Employers will not care where you trained - and if 'going to Cambridge' is more important to you than working as a doctor, you might like to rethink this as a career.

Yep.

I go private that’s why I’m wondering because I need to be at the top of my cohort

Really? Although I didn't apply for oxbridge, from what I understood, all my friend did was get a very high UCAT and did reasonably well at interview