Things to do on Carnival Imagination and in the Bahamas?

Ok so I'm going on my first cruise and need some tips??? anybody that has been on a cruise to THe Bahamas please give them to me? what can I take to keep from getting sea sick? does it really matter if I get a cabin with or without a window? what level is good to be on, what is considered too low? I have been told to visit the Atlantis, can you do that if you are not staying there? are there any nice clubs in the Bahamas for African Americans? If you buy alcohol in the Bahamas can you bring it back to the US? are there any Adult only places to go on the island?