[LT Guppy]

Pretty sure I'm the only one in the community on this site...

As an MC you'll do three basic things - writing stories, photography, and video. Depending on where you are stationed will influence how much of what you do.
There are specialized NECs you can get (graphic design, broadcasting, to name a couple), but in general you will learn at least a little of everything.
Most MCs will go straight to a ship (usually a carrier or big deck amphib). Yes, your spouse can come with you. Some MCs will go to a shore-based sea duty. Basically, you're not assigned to a specific ship, so you get loaned to a smaller ship for their deployment.