you need to press the reset button just above where the power cord plugs into the back of the router.
If you are not getting any lights on the router when you plug it in that means the router is not getting any power and that can be caused by using the wrong power adapter, a bad power adapter or cord, the power adapter itself is unplugged, the wall socket is faulty, or the router itself is damaged.
I was trying to change my IP address in the settings and messed of messed something up because then the light went red and it couldn't connect to the internet anymore. So I unplugged the whole thing, then replugged it, but it wouldn't even turn on. Is there any way to return it to the factory defaults or whatever so it will turn on again? Please help.