Open the Facebook app or go to facebook.com and log in
Tap/click your profile picture to open your profile
Tap/click the three dots (more) or View profile information
Select Settings and privacy
Choose Settings
Find and select Personal details (or Name)
Select Name
Enter your new first name and last name
Click/ tap Review change
Enter your password (if prompted)
Upload documents if Facebook asks
Click/ tap Save changes
Wait for approval if required