Your a newbie so your not stupid.
Your house battery is used for starting your Gen but its also use for all 12v control boards in your RV.
We have people asking do I leave my battery cut off switch on when hooked to shore power.
The reasoning I would guess is the converter is supplying do 12v to systems to operate so why do I need the battery.
The reason is the battery needs to be charged by the converter and its also charged in some coach's by the engine alternator.
When ever you use the coach you always leave the battery system in the picture for all power requirements the time battery is not is when you winterize shut down use of coach by operating a battery cutoff switch or removing the battery during winter months.
My coach is plugged in all the time to house so house batteries are kept at full charge plus in my charging system it also keep my chassis engine battery fully charged.
Some of the links provide in this thread
will bring you up to date on your power systems in your coach, read them for further education and you will have a better understanding of you new hobby.