Just met with a Navy recruiter, need help with some information?

I met with a Navy recruiter today, which was informative, but now I'm a little confused. He talked about the DEP, college and how the Navy will pay for it, the ASVAB, and possible deployment locations. What I am confused about is the daily life of a Navy man. If I get deployed, what will I be doing? Say I am in Italy, and am in a medical MOS, what exactly would I be doing a the base? I also feel a bit silly for asking this, but do I have to go on a submarine? What determines if I do or don't? I plan on seeing the recruiter again, but I urgently need an answer to these things. Thank you.