It used to be that you could sit for RN board, not now. That was when they had a long Charlie and short Charlie course (what LPNs/91C used to be called, before they were changed to 91W, I just dated myself).
You still have to get credits for the required classes for what ever nursing school you apply for. I can tell you from experience that the 91W course doesn't give you a lot of individual college credits. Even with your ACE transcripts and your DD214 it doesn't add up to a lot. Your gonna have to get a lot of outside core credits that the military doesn't teach. ANd then take the nursing courses. If you can afford it or can handle the workload, take an online class for any core credits or nursing credits that you need. Look into something like Excelsior Nursing>