Can some one that has knowledge about Salt water fish tanks help me out?

I recently received a 50 gallon fish tank and i was wondering what i need to do to get it all started. i want salt water fish with coral and live rocks. but i don't know how to go about starting it. i have a few fish in mind that i would like to put in, but i don't know if they'd live comfortably all together. i don't think they'd all fit in the tank at the same time. if they cant which ones would be able to live comfortably in the tank. the fishes i am thinking about are a snow flake eel, mandarin dragonet, White frog fish, Box Fish, Puffer fish, Clown Fish,and Lion Fish. Can Any one help???? I think Im Rambling, so if someone can just tell me what kind of equipment i need?, how much coral or rocks i will need? is sand or pebbles better? and will the fish go with the tank size? Or any other advice it will all be appreciated. thank you.