(1) Can you speak english? Like well. If yes, proceed to last line
(2) What you do in clinic has literally NOTHING to do with what you do in the CS exam. You must go through the motions, doing everything the way they want it done. No shortcuts, no logic, just wrote memory. Most patients are adults. Most patients are medicine. The "peds" patient I had was 17. Having missed some cores means absolutely nothing.
(3) First Aid CS is designed for the FMG. Its perfect. It tells you what to do, in what order, and if you can memorize well, literally everything you should ask and do. If you are worried about failing, get a study partner and go through every case twice. This is MEGA overkill for studying, but if it will be your barrier, practice hard. It should take you about 2 weeks to do every case twice.
(4) Step 2 CS is a joke exam and you will rock the socks off it as long as you speak english