Just bought my first RV a week ago. No idea what I am doing!

When I turned the valve on the LP tank, I heard the gas start moving, but the camper just started to small like gas.

I would address this FIRST - you have a gas leak someplace - find
it fix it before you light anything.

Furnaces/water heaters/fridges generally do not have manual pilot light. All mine had a piezo spark to light the appliance, so no standing pilot light (except the oven).

But FIX THE GAS LEAK FIRST