Connect the modem router to the line splitter with a coaxial cable. Take the power adapter and plug it into an electrical socket. Wait a second until the power LED and the internet LED are both solid green. Now you must link your modem router to a Wi-Fi device or a computer. The ethernet cable is required for a wired connection. Also, use the network name and password listed on the product label to connect to Wi-Fi. To log in to your modem router, open your web browser and go to routerlogin.net. Following that, you'll be asked to enter your login name and password. The default credentials for the user name and password are "admin" for the user name and "password" for the password. https://prompthelp.us/blog/netgear-nighthawk-ac1900-modem-and-router/