OPPO] Are basic smartphone operations such as "back" a swipe or a button tap?

System navigation is a function related to basic operations of Android devices, such as "Return to previous screen," "Return to home screen," and "Show recent tasks screen," etc. In the case of OPPO, "buttons" or "gestures" are selected during the setup process. You can review the selection from [Settings] ⇒ [Other Settings] ⇒ [System Navigation], so you can always change to the one that suits you best and is easier to use.
In the case of gesture navigation, you can easily turn it into a floating window.
For button navigation, you can add user assistance function buttons to the navigation bar.