ACT Math Review Help!

I was wondering what website I should use that could help me with ACT math prep. I’ve forgotten most of the concepts and I pretty much need to relearn most of the concepts. I’m interested in getting a Magoosh account. What are your thoughts? Also will taking multiple practice tests help me learn the concepts or will they just help me learn how to do that one specific problem? Thanks!

@APUEducation I thought Richard Corn’s book is quite good. You can also try to buy the ACT online prep.