Cruise ships often hold 3,000-4,000 guests plus another 1,500 or so in staff and crew.
You can if you'd like to work on a cruise ship. Cruise ships are like cities: there is quite a variety of staff required.
Careers in the cruise ship industry:
Ship's Control Room
Deck Crew and Captain
Most ships, ironically, have several pools and offer swim lessons and water games
Beautician or Barber
On Board: Fine dining with a view of....the ocean. Lots and lots of ocean.
Working for a cruise line means, of course, that you will live and work on the ship, probably for months at a time, as you work one cruise after another. You may prefer that type of life----no homeowner issues, and you really don't need a car. You will have activities to do in your off-duty time, and access to the same amenities offered to the passengers.
However, you may find that being constantly 'away' does not suit you. It depends on how independent you are and if you like to keep moving from port to port. If this sounds like your 'thing,' then think about living a life on a ship.
Here is more information about what it's like to work on a cruise ship:
A guest bedroom onboard. With a view of....you guessed it: The Ocean.
Ship staff, except the officers, sleep in bunks like this: smaller than some college dorms
Think about a life of travel and learning by working on a ship. It might float your boat!