By default, the Photon OS comes with 2 pre configured network configuration files.
First of all, list down the network interfaces with the command networkctl
Then, based on your network configuration you may select the relavent configuration file (Static IP – eth.network | DHCP – dhcp-en.network). You may have to access the network configuration related directory.
Edit the Network configuration appropriately
The changed configuration will look like this below
Save and restart the networking services
systemctl restart systemd-networkd