From your Mobile device:
Facebook Mobile has two different versions of settings based on when you created your account. They are Account Settings and Profile Settings. Below you will see the steps for each version based on the options you have once you open your Facebook settings.
Facebook Mobile App
Open the Facebook App
Tap menu at the top right corner for Android users or tap your photo at the bottom right for iPhone
Tap the gear icon at the top right next to the magnifying glass
Under Meta Account Center, tap Personal details
Tap Personal details
Tap Account ownership and control
Tap Deactivation and deletion
Select Delete account
Tap Continue to account deletion
Tap continue and follow instructions to confirm account deletion
DEMO - Delete Duplicate Profiles
From your computer:
Go to www.Facebook.com and log into your account
Click on your photo at the top right of Facebook
Next, click on “Settings and Privacy”
Then, click on “Settings”
Then, on the left side Settings menu, under “Meta Accounts Center” click on “Personal details”
Click Account Ownership and Control
Click Deactivation or Deletion
Select the profile to delete
Then click to continue and follow instructions to confirm account deletion
DEMO - Delete Duplicate Profiles - Computer/Laptop
NOTE: This is permanent and you will not be able to retrieve any information from the deleted account. Make sure the duplicate profile is the correct account you are deleting before performing this step as you will not be able to get it back.