First we select „Manual Configure“ in the web interface:

After that, we determine how the router should establish an Internet connection. Here we change from „Dynamic IP (DHCP)“ to „Static IP“:

Now comes the decisive step. Here you set which IP address, subnet mask and DNS server the router should use. Attention: Please do NOT use the data from the screenshot, but enter the data that you received by e-mail! The official HRZ DNS servers can be specified as DNS servers, or DNS server of a third-party provider.

Lastly we configure the Wi-Fi network. It is important to set a sufficient encryption (WPA2, if possible even better WPA3) and a complex password. It is also recommended to choose a unique Wi-Fi name.