OnePlus Nord
Android 11.0
Select help topic
1. Find "Phone ringtone"
Slide two fingers downwards starting from the top of the screen.
Press the settings icon.
Press Sounds & Vibration.
Press Phone ringtone.
2. Select ring tone
Press Ringtone from Internal Storage.
Press the required ring tones to hear them.
Once you've found a ring tone you like, press arrow left.
3. Return to the home screen
Slide your finger upwards starting from the bottom of the screen to return to the home screen.