Tests can not and do not measure your intelligence, but they do inform you very precisely on how well you can answer questions correctly within a short span of time. Test taking is a skill that takes hours and hours of practice till one can finally become proficient in it. Even though this skill might be totally pointless in regards to your journey as an individual, you still need it to get from where you are to where you want to be as it pertains to college.
Below is a site that can help you rigorously practice for the SAT:
Start grinding at KhanAcedemy