Help me in a level choices- i am surely having: ict comp. science maths english but im confused about these subjects : bio chem physics ,further maths -- im more towards mechanics and programming,design
Well, to become a Mechanic(al engineer) you're gonna need Physics and Maths at a minimum. ICT or CompSci wouldn't be bad as a third. I very seriously don't suggest taking more than 3.
Sure thing. Essentially it's an extension of Maths A Level where you learn about more in-depth, abstract mathematical concepts, which generally ends up getting to 1st year university level. For most schools you do Maths A Level in one year and FM in the second.
That said, it's extremely difficult, not least because you have to do regular Maths in one year. The only people that really need it are people going to study Maths at university, or at some very high-ranked universities like Oxbridge or Imperial.
AND what do i need i i want to become a video game designer , programmer
For video game design there are courses designed for that, I don't know exactly how effective they are at getting you into the market but they exist. Far as I know generally they're not super concerned what you took if you can provide a portfolio etc.
Programming will generally require a Software Engineering or Computer Science degree where the focus is by and large on coding and programming for your entire degree. You'll need (regular) Maths A Level normally, but CompSci/ICT is looked at positively. A few places also need FM.
If you take Math A Level, try to do the Decision Mathematics modules (D1, D2) because they're most relevant to your aims.