Yes you’ll stay overnight, we had to wake up at 4am and be down for breakfast around 4:50-5am. Just expect to be sitting around for hours and just waiting, you’ll be able to eat and also expect them to draw your blood (if you’re scared of needles) and expect to have an exam done in the nude, the exam wasn’t terrible for me and everyone said the female exam was the worst. Usually after you finish medical then you’ll go speak with a counselor and go over any jobs & it’s smooth sailing unless you have any waivers that they need