assuming the IP addresses of your devices begin with 192.168.0.X, the first three numbers (192.168.0) must all be the same for them to be all on the same LAN and can talk to eachother. the last octet (the last number in the IP address) will be a number between 1 and 254. for example, if a device connected by Ethernet has a 192.168.0.10 and a WiFi device had a 192.168.1.10 IP address, they cannot talk to eachother on the same LAN