Depending on the make, you can use the cameras software tool to locate the cameras ip address. Then use a browser to go into the cameras interface using the ip address and from there select network and you should see the option in there somewhere. If you have a Dahua camera for example the default ip address is 192.168.1.108.
Or if you have already plugged your camera into your network you can look in your attached devices from within your modem / router to see if it has obtained a DHCP address and again enter that address into your browser
You should also be able to view the router's interface and see what IP addresses are signed to what MAC number. Your IP camera may have a sticker on it showing the MAC number which should be assigned to the cameras ( sometimes they do mislabel products so it is not 100% accurate )