Should i firm my uni of nottingham mpharm offer?

So basically i'm resitting, got bcc last year in chem, bio and maths in that order. i applied with predicted aab, and got an offer which says subject to getting aa in bio and maths. my question is will i be rejected on results day if i get the two a's in maths and chem instead of getting it in bio :/ or does it not matter where i get aab since the website said grdes needed for mpharm is aab???

If you were to achieve AA in Maths and Biology, as requested, then your overall grade profile would be AAB (using your achieved B from Chemistry last year).
If you were to achieve AA in Maths and Chemistry, which is the scenario you've suggested might happen, then your overall grade profile would be AAC (using your achieved C from Biology last year)
That would meet neither the entry requirements as stated on their web site, nor the conditions they've stated in their offer. They would therefore be under no obligation to confirm your place. Whether they opted to do so anyway would be a function of how many spaces (if any) they had left after having confirmed the place of offer-holders who had met their offer conditions.

Even if im resitting all three and not just bio and maths?

In the theoretical scenario you've outlined, "i get the two a's in maths and chem instead of getting it in bio", what grade do you get in Biology?
If it remains unchanged from last year, you have AAC overall, which - as I've said above - meets neither their typical entry requirements nor your offer conditions.
If you manage to lift your Biology grade to a B then you have AAB overall which does meet their typical entry requirements, but still doesn't meet your offer conditions. So they still wouldn't be obliged to confirm your place. However, they're more likely to than in the AAC scenario above.
It's also worth pointing out that in recent years they've confirmed the place of 85% of offer-holders who achieved AAC (see "How do you compare?" on this UCAS page), so history would suggest that your chances are good. But unless you meet their specific offer conditions, then you might be unlucky.

Yes sorry i should have made that clear, i am predicted a b in biology and i feel im more likely to get a's in maths and chem than i am in bio
Anyway thank you for the info, i didn't know that how do you compare website existed thanks!!