@dllssn23 

You would be able to log into the router even if there is no internet connection. Rather then using the URL, use the default IP address of the router which should be 192.168.0.1 or 192.168.1.1

Make sure you are in fact connected to the router either with a Ethernet cable or by being connected to the routers Wi-Fi.

If you look at the internet icon, what is the staus of it? What color if it is on?