Apps use the selected region to provide country-specific content, and under ColorOS the region can be quickly and easily adjusted in the Oppo smartphone's settings.

However, changing the region does not affect the Google Play Store or a country block on, for example, video streaming services.

Android 10 | ColorOS 7.0
Step 1:  Open the  Settings
Step 2:  Tap on  Language & region
Step 3:  Tap on  Region
Step 4:  Choose desired  Region
  1. Open the Settings
  2. Tap on Language & region
  3. Tap on Region
  4. Choose desired Region

Oppo Instructions