In all college admissions, if you have specific schools you wish to apply for, you should check with their admissions departments. Many schools have specific requirements or preferences, and it is ALWAYS a good idea to take all "recommended" tests as well as those that are required if possible. That said, most prestigious universities in the UK will take your levels and allow you to take in-house tests for other placements. Canadian universities are less consistent in terms of policy.

HOWEVER, preparing for and taking multiple tests will NEVER hurt you in college admissions. Taking the SAT will not only allow you to apply to most any school worldwide, it can also help your admissions chances by demonstrating yet another way you have excelled academically (assuming, of course, that you study and do well). If you do well on your A-levels, the SAT will serve as another reminder and will be helpful if you decide to apply to many Canadian or American schools. However, should you receive lower scores on your levels than you anticipated, a good SAT score will definitely help you out.

put it this way what do you wont to do which one do u really wont to do then do it