If we contact a stored contact on the OnePlus smartphone more often, it can be marked as a favorite to ensure quicker and faster access, as it is displayed at the top of the Contacts app, for example.

Note: In the same way that a contact is marked as a favorite by means of a star symbol, we can also remove the favorite again.

Android 10 | OxygenOS 10.0
Add contact to favourites -  Open the  Contacts app
Add contact to favourites -  Choose a  contact
Add contact to favourites -  Tap on  Favourite
  1. Open the Contacts app
  2. Choose a contact
  3. Tap on Favourite

OnePlus Instructions