OK, serious answer.
Accomodation - during basic it'll be messdecks with 20+ others. As you progress into the fleet it varies. Most ships it wll still be large mess decks, with a pit (a bunk) to call you own and a couple of lockers. The latest Type 45 destroyers you'll share with up to 5 others.
Nowadays there's satellite TV, internet access etc so you're well in touch with home. Ashore, increasingly you'll be in a single cabin.
What does an OM do - have you taken a look
here yet? Others on the site can tell you more.
As for Officer, horses for courses. They'll look for different things to be a RN, Army or RAF Officer. I wouldn't say it was easier or more difficult, just different. It depends on what temperament and personality you have, you may find you fit better in one or the other.