With DJI RC-N2:

Connect your mobile device (connected to the internet) with the remote controller, and then connect to DJI Mini 4 Pro via the DJI Fly app. Follow the instructions in the app to activate DJI Mini 4 Pro.

With DJI RC 2:

When using DJI RC 2 for the first time, connect to the internet via Wi-Fi or a smartphone hotspot, and then follow the instructions in the DJI Fly app to activate the device. After activating DJI RC 2, connect it with DJI Mini 4 Pro via the DJI Fly app, and then follow the instructions in the app to activate the aircraft.