|Connect a PC to the router via Ethernet cable.|
Go to start, type cmd then press enter.
In the black box type ipconfig /all
Look through the list of information that shows up.
Under Local Area Connection,
Find Default Gateway and look at the IP it shows.
It should be something like 192.168.x.x where the x's are numbers.
Type that into the address bar in your web browser.
There you should be taken to your routers page. Where you can access your settings for passwords or whatever it is you need doing.
If that's not what you want, you need to make your question or problem more clear.