Sweepstakes, are you looking for Reg Force (full-time) or Reserve (pt)?
That will make a huge difference in the answer.
If Reg F, the army will teach you what you need to know; meet the entry requirments, study hard, listen to your supervisors, and learn what you need.
If Res, you'll learn a bit, but not a huge amount, of emergency medicine, you'll have an opportunity to maintain the skills you'll gain, and you'll work under supervision for a while. Non-licensed reserve medics have a fairly restricted scope-of-practice. If you've got a civi license, you operate to the level of your civilian protocols, you can go overseas, work in CF clinics, spend lots of time in the field, etc.
Hope this helps, feel free to ask if there's anything else you need.
DF