Adding a router to your Ethernet in your apartment should be relatively easy.
You will need to connect the INTERNET or WAN port to the provided Ethernet wall port with an Ethernet cord.
Next you will need to configure your router. Important settings are that your router needs to be setup to receive an IP address automatically or DHCP. You will also need to use the setting to get DNS from your ISP.
Once you have setup your router you will need to try and connect to a website with your computer and you should receive our login screen. At the login screen you will enter your credentials (Username and Password), press enter and you should receive a success screen telling you to reboot your equipment. At that point you will need to power cycle your router. And once it has restarted you should be able to access the Internet.
Here is a short video that all take you through the process: