Apple iPad Pro 12.9 (2020)
iPadOS 13.4
1. Find "Text Tone"
Press Settings.
Press Sounds.
Press Text Tone.
2. Select message tone
Press the required message tones to hear them.
Once you've found a message 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.