You need to connect to your router’s wifi with a mobile device, then download app D-Link WiFi, then enter the settings in the app, register a D-Link account, and proceed to downloading D-Fend. Then, in the D-Fend app, you will be able to tap on every device in the router’s network and install McAfee on them - tapping that option will ask you how would you like to send an installation link to that device. Then just proceed with the installation on each device. Below screenshots from D-Link D-Fend app: