What kind of camper (trailer, 5er, RV, something else) Was this a factory installed generator? Have you used this in the past? What other electrical equipment is installed? Did you check the connectors to make sure they are wired correctly? What was on when you made the connection? What kind of generator (brand & model and/or ratings)? With the electricity off, have you found out what smoked? Do you have a surge protector? There are so many possibilities at this point.
Sorry about so many questions, but you've got to try and "put us there"
I Have a new 5th wheel the genarator is a portable 12 kw with a30 amp 120/240 plug on it . I had a plug built to get back to a 50 amp rv plug. Non of the fuses or breakers blow or where hot to the touch. I can't find there the smoke was coming from it started as soon as I pluged it in
Sounds to me that the plug may be wired wrong and shot 240 to the rv and created a short. A 120 Volt rv plug has 1 120v line a neutral and a ground. A 240 plug has 2 120V lines a neutral and a ground in most cases. If the 50 Amp 120v plug was wired how it sounds, it went into the rv with 2 120v lines and a ground. thus causing the short and smoke.
The improper wiring can have caused anything that was on at the time to blow, starting with the power distribution panel. If nothing else was on at the time, then they would not have been trying to draw power and therefore safe from harm.
The chances are good you'll only need to address the area where you saw smoke and the power distribution panel, because it sounds like the damage will have been localized there. If you are the type that leaves anything on when "unplugging" those items could be toast too. Whatever you tried to turn on could be damaged, too.
It is hard to say what you may have burnt up. I would FIRST check the plugs wiring and see if in fact it was wired wrong so you know what you are working with. IF the plug WAS wired correct the next possible issue is defective RV wiring from new. You stated it is a new 5th wheel, did you ever have this hooked up before?