Wow...lots to explain here!
You really may want to call a local RV place so they can explain things to you. You might have to pay a fee but you will get a great education. Also, when people buy an RV from a dealer the walk through usually takes up to four hours. We just bought our second Class A RV and this walk through took about two hours. With all that said, I will try to answer some of your questions.
When you start the generator, there is an automatic transfer switch so you shouldn't have to do anything. One thing to consider; turn your air conditioner/s off when starting the generator then wait about a minute or two before you turn them on. That's because if you have the air conditioners on when the transfer switch switches from 'shore power' to 'generator power' that is a heavy load on the generator.
The Battery Disconnect button/switch is used for storage. You would disconnect your batteries when not in use to help extend their lives. Incidentally you will have at least three batteries depending on your coach and you will wnat someone to check them for you. There is the Chasis (engine) battery which is the same function as your car battery. used to start the engine, light the head lights, etc. But then you have some house batteries which will run most of the lighting inside the coach.
Another thing to consider fer getting educated is there are a bunch of really knowledgeable and friendly people here. if you tell people where you are, you might be able to arrange from someone form the forum to come help you out. I know if you were near me, I sure wouldn't mind helping you!
Good luck!
Oh and welcome to RVing and welcome to the forum!
2006 Fleetwood Pace Arrow 37C
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