How to Enable Call Forwarding on your Android phone app:
Open the Android native phone app (the green one, not Nagish)
Tap the three dots in the top right corner to open the menu
Select Settings
Tap Supplementary services
Tap Call Forwarding
Tap Always Forward
Enter your Nagish number
Tap Enable
After call forwarding is set up:
Open the Nagish app
Tap Settings
Tap Phone number
Tap Verify my connection > Receive a 'Success' message. You should be all set 🥳