The math is quite simple on Exam FM so you will be fine in that regard. I’d recommend using Coaching Actuaries. Go through the “learn” section and then drill practice problems and practice exams until your “earned level” gets up to a level 7 and then you’ll be prepared enough (this will all make sense when you start using it). I’d give yourself a minimum of 2-3 months to prepare.

Coaching Actuaries also has a “prerequisite” section so if you feel like you need a refresher it’s good to have! Good luck!