Welcome Tom to the forum.
will give you many answers and the ones below in my signature also.
All your batteries will be charged by your B.I.M. charging system while plugged in and driving by your alternator.
If you have AGS off your Gen it will auto start the Gen to charge your batteries.
The large link I just gave you has three 2018 NA's bt Idelup, turbopilot and cyre that explains many items on your coach and there functions and many of the problems they had have been corrected by them or Newmar, many New Aire owners now enjoy a great coach.
You have instructions on slide use and I would follow them hopefully your PDI was a good one by dealer, if you have any questions just ask on forum before doing something if you do not under stand something,all questions on a new thread not tail end of someone else thread.
Any time you use coach BCO is on and coach is plugged in even at home to at least a 110 outlet to keep batteries fully charged.
When moving slides always have plugged in or Gen on to supple a good 12v for motors and pump and check your reveal of your FWS.
Just a few items to stay out of trouble, enjoy your coach and safe travels.