Need help about my A levels

So i find myself in this hard decision. My school does not provide a2 maths because i was the only one that passed so they essentially cant provide a levels maths just for one student. So the alternative choice is to go to a different school 3 times a week for maths which is further away and is very annoying since i still have lessons during those days at my school. The thing is i need a B grade in a level maths to get into uni i want. Can i even self teach myself a2 maths which would be C3 C4 and M1 and do those exams. Im really unsure what to do. Any advice?