We can set the start time, from when the OnePlus smartphone's screensaver should start.
We have the following options to select:

Note: To disable the screensaver completely, we simply select the default option "Never".

Android 10 | OxygenOS 10.0
Step 1:  Open the  Settings
Step 2:  Tap on  Display
Step 3:  Tap on  Screen saver
Step 4:  Tap on  When to start
Step 5:  Choose an  option
  1. Open the Settings
  2. Tap on Display
  3. Tap on Screen saver
  4. Tap on When to start
  5. Choose an option

OnePlus Instructions