SAT prep

Hello everyone. I’m currently trying to study for the SAT test, especially the maths section. I’ve taken all the quiz’s to determine what level of maths I’m currently at, but after that, it throws me into the deep end without showing me where to start. For example, it will give me the next subject to be algebra. And straight away it tells me to solve an equation. It haves 2 example videos and nothing more. Doesn’t explain how to solve algebra of any sort. So my question is, am I doing this correctly? There’s allot of maths I don’t understand and therefore am struggling straight away with studying. I understand Khan Academy have maths courses separate from the SAT course. Do I need to single out, every single bit of maths that I don’t understand and do the individual course on khan academy, then go back to the SAT prep? Please help. Thanks, Jay