STEM a level options

Im doing gcses right now and my options are computing, ICT and product design.
For my A levels i want to do 3D design and an IT based course however i also wanted to do a computer science course for the coding but after looking into it most people are saying that universities look for math and science/physics a levels instead.
So i cannot decide what a levels to choose as i think i want to do a stem based subject but there are too many for example in maths there is normal maths, core maths and further maths and the same for IT there is so many different a levels, some are level 3 btecs and others are A/As and honestly i have no idea what any of these things mean 😂. Plus in the college i want to go to you can only do 4 subjects in the first year but you have to drop one and i know you cannot drop certain subjects.
So if anyone has done one of these courses or is going for a stem based subject, any help is appreciated.

Maths is useful and required by top universities to study Computer Science, ICT A level isn't strictly relevant to Computer Science although isn't bad to have, Computing is good and will give you a good grounding to study Comp Sci, Physics is good too as it improves your maths abilities although isn't required for any Comp Sci degree and probably wont feature too much in Comp Sci degree modules.

BTEC IT or BTEC Computing or BTEC Comp Sci are good too for Computer Science as they are likely to include programming modules. I did the BTEC Level 3 in IT and went on to study a BSc and MSc in Computer Science and I also work as a Software Engineer.

Does the BTEC Level 3 in IT take up 2 a level options