Headlight Relay Kits

I see one plug to power it. That plugs into the driver side stock light female socket, then the new plugs go to the new headlights and the stock passenger female socket is not used?
That's correct as the drivers side is all that matters, the factory wiring is the same , ties in to drivers side and runs to passenger side , an it all ties thru floor dimmer switch as well for hi/low