In order not to oversleep an alarm clock, we can set the alarm volume on the OnePlus smartphone individually and independently of the selected volume for media such as apps or games.

A slider is used to set the volume of the alarm tone in seven different levels.

Android 10 | OxygenOS 10.0
Alarm volume -  Open the  Settings
Alarm volume -  Tap on  Sounds & vibration
Alarm volume -  Swipe  left  or  right  to set the  alarm  volume
  1. Open the Settings
  2. Tap on Sounds & vibration
  3. Swipe left or right to set the alarm volume

OnePlus Instructions