Should I self-teach A Level Maths

Hi , I wanted to know if I should and can be able to teach myself A level maths, for reference I want to study Computer Science at top unis, I got an A* in GCSE Computer Science and sadly got a B (6 marks off an A) in maths which meant I couldnt pick it for A Level. Trying to go to top unis in 2 years time i realise i would need a level maths no matter how strong my computer science a level grades will be.

How would I go about learning A Level Maths, I did Edexcel for GCSE so preferably i'd stick with Edexcel A Level Maths, does anyone know any resources I can use, how i would go about entering myself as a candidate etc.

I currently do Computer Science, Economics and Philosophy at A Level (I have no real interest in philosophy but I got an A* in both English Literature and an A in RS so I figured why not) , not a fan of essay subjects I love subjects like maths and comp sci to death.