A* in further maths

I'm aiming to get an A* overall for further maths. I have completed the first year and got 211/300 ums so that's just about a B. I plan on retaking two units (d1 & m1) but i was wondering if i didn't retake and got an average of 90% for my a2 units would i still get an A*?

You need 480/600 overall and 270/300 in A2 units to get A*.
So yes you could get an A* without resitting.

Where can I confirm that I need 480 overall and 270 in my a2 units?

What do you mean confirm? As in proof that those are the requirements?
Look at your exam board's website for further maths.

Yeah I mean proof and I forgot to say that the exam board is edexcel