Most yachts have a (small) area, usually in the front or bow of the boat, that is designated for crew. This may consist of a common area, a small galley (kitchen,) and also all of the crew cabins.
Crew don’t typically hang out in the parts of the boat where guests chill, even if there are no guests on board. Also, guests don’t typically come in the crew quarters either.
Crew cabins (bedrooms) are nowhere near as nice or big as the guest cabins or staterooms. You can expect to share a tiny cabin with at least one other crew member, although in some situations you may have your own.
You normally have no say in who your roommate is, or whether they’re the same sex or not.
Some boats may have a crew house that is nearby that they rent out for the crew to stay in. Especially if the boat is in a maintenance or yard period. This would probably be preferable to having to live on board but I’m sure it all depends on the situation.
The crew cabins and heads are very small, and are usually located below deck in the bow of the boat. There’s usually a bunk bed, a small closet space, a TV,and a small head (bathroom.)
You should be considerate of your roommate and try to keep your area clean, organized, and not to be loud while they are sleeping.
Although you’re living on board full time, you can’t expect to treat it like your home. In my experience we couldn’t bring any friends or family on board the boat unless we had permission from the captain to do so.
Some boats don’t allow you to drink alcohol on board, these are called dry boats. You will likely learn during the interview process if the boat is a dry boat. All boats have their own rules, be sure to learn them and abide by them.