The first thing about the generator is that you need to retrieve the manual from the cabin lift stop ( it's the door with the bloody hand sign on it), to do that you need to put the generator in sleep mode (to avoid been fried by the broken cables outside), then climb the wall to get to the roof and enter inside from there.
Once done read how the manual work.
Find the gasoline to refuel the generator ( turn left when you go to the main road) and go find the fuel station ( you will need two days to complete everything).
First thing is to enter inside the office, fight the shadow you will find there, and activate the fuel pumps; then got outside free the pump from the vines ,and put the gasoline in a can that you will find inside the fuel station.
Once you did everything, you should spend the evening with the girls (Mia, that you should have saved from the lodge hotel and Robin) reading how to repair the cables and, after you practice with them one evening with some cables taken from the lamps, the morning after repair the cables at the cabin, refill the generator and you should be able to go.
If you need more help or a save let me know.