My inverter kicks in as soon as I disconnect from shore power, and switches to charging when I hook up again.
Hard to say what your setup is, automatic or manual.
As far as what outlets are connected, no way to tell from here. Maybe ask the previous owner, or hire an electrician.
2013 KZ Sportsmen Classic 200, 20 ft TT
2020 RAM 1500, 5.7 4x4, 8 speed