Open the Facebook app or go to https://www.facebook.com
Log in if you’re not already logged in
Tap/click your profile picture (top right)
Select Settings and privacy
Tap/click Settings
Select Password and security
Choose Change password
Enter your current password
Enter your new password
Tap/click Save changes (or Update password)
If prompted, enter a code sent to your email or phone to confirm
Save the new password and log in again if required