dinksy

Hi, My dad just died & I now have a 1987 Chevy motorhome that my dad always drove & parked @ camp grounds for me 2 use. I tried to park it in driveway for kids to campout in. I couldn't get power to it. Is there a switch i have 2 hit so the alternator will power the aux. battery? Please help. my dad just died & I'm trying to not let my kids notice & keep things the way they always been.