Any notification enabled on your phone will be sent to the Garmin device. Specific notification categories can be enabled/disabled from your Garmin device settings. See I Am Having Issues with My Automotive Device After Updating to iOS 13 on My iPhone if you have issues after upgrading to iOS 13.
1. Open the Garmin Drive app on your phone and set your phone to Find Me/Discoverable mode
Refer to the owner's manual of the phone if you are not sure how to set it to Find Me/Discoverable mode.
2. Touch Settings on the Garmin device
3. Touch Wireless Networks
4. Touch Bluetooth
5. If the Bluetooth switch in the upper right corner is disabled, touch the switch to
enable it
6. Touch Navigation Device in the Garmin Drive app
7. Touch Find Garmin Device
8. Touch the name of the Garmin device from the list of compatible Bluetooth devices in the area
9. Touch PAIR if prompted on the Garmin device
10. Touch Pair on the phone if prompted
11. Touch Sign In. Touch Create Account if you don't have an account.
12. Enter your email and password and touch Next
13. Touch Enable Notifications
14. Touch Allow
15. Enable Allow Notifications for the Garmin Drive app in iPhone Settings
16. Touch Apps on the Garmin device
17. Touch Tools
18. Touch Smart Notifications
19. Touch the wrench icon
20. Select the notifications you want to receive
21. Touch Save
You will now be able to view or listen to notifications from your phone on your Garmin device.