Before you can access your router admin panel using 192.168.1.1, make sure your PC are connected to your router.
Verify your router ip address (default gateway) is 192.168.1.1, see this guide to find your default ip address http://19216811-ipaddress.com/find-router-ip-address
Follow this instruction how to login 192.168.1.1:
1. open web browser and type 192.168.1.1
2. enter your router username & password
See in this web page for the details http://19216811-ipaddress.com