Sounds like you could have two problems. I can only go off my guess based on how my rv is setup. If you have no 120 volts from shore power or generator then you could have a bad transfer switch. If you have no 12 volts to your lights, from the batteries, then you need to check your batteries to see if you have voltage.
You also have 120 volt circuit breakers inside the coach somewhere and on the generator.
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