1, the router checks the port number. Unless it is a large router or a network exam such as CCNA, it will generally exist in the router simulator or exam instructions. Your question is not clear.

2. Check the port number. Windows and Linux usually use the netstat command. Take Windows as an example, as shown in the following figure.

3. Check the IP address of the router. In this regard, you only need to execute ipconfig /all in Cmd and find that "gateway address" or "DHCP server address" is the IP address of the router.