If the "Virtual Buttons" are activated on the Oppo-Smartphone, the key combination can be changed:

In addition to the three-button navigation, there is also a two-button navigation. Here the "Last Apps" button is omitted. To access this, the Home button must be held down or wiped up.

Android 10 | ColorOS 7.0
Step 1:  Open the  Settings
Step 2:  Tap on  Convenience tools
Step 3:  Tap on  Navigation buttons
Step 4:  Choose desired  Layout
  1. Open the Settings
  2. Tap on Convenience tools
  3. Tap on Navigation buttons
  4. Choose desired Layout

Oppo Instructions