First only plug one camera in at a time. All Dahua cameras come with a hard set IP address of 192.168.1.108. There are two ways to get to the camera to change the IP.
1 - Change the IP of your PC to 192.168.1.xx, anything but .108. Then plug the camera and the PC into a PoE switch, bring up Internet Explorer and type 192.168.1.108 in to the address bar. That will open the GUI of the camera and let you initialize it and sett all parameters including the network IP address. To get to Internet Explorer in Win10 just type "Explorer" in the search box on the tool bar.
2 - Use the Dahua config tool to access the camera directly, without changing your PC IP address. You will need to download that tool and when you run it be sure to set the IP range for the search to 192.168.1.1 through 192.168.1.200. That will let you change the IP address to match your local IP scheme.
Do not connect to video cameras through a router. ISP/consumer routers do not have the bandwidth capability required for constant, multiple, video streams. All cameras and the PC used for monitoring them, or your NVR as the case may be, need to be on the same switch. That switch can connect back to your router so you can access the internet from the PC or monitor remotely from other PCs. All cameras should have fixed IP addresses and not use DHCP.