Helpful guide
You can change your Facebook email ID through the service’s Settings menu by adding or removing email addresses from your account. See: How to Recover a Deleted Facebook Account
Change Your Email ID on FacebookYou can add or remove the email addresses and phone numbers that you use to log in to your Facebook account and receive messages on Facebook.
Use the Settings Menu to Change Your Contact InformationTo do this, click the menu icon in the top-right corner of the Facebook website. Then, click “Settings.” See: Steps on How to Delete or Clear Notifications on Facebook
Add New Email AddressesAdd new email addresses by clicking “Add another email or mobile number” and typing in your email address. When you add a new address, you may be required to confirm your Facebook password and to click on an email that Facebook sends you to verify it’s the correct address, and you will have access to it.
Remove Old Email AddressesIf there are any email addresses you no longer want associated with your account, click the “remove” link next to each one.
Choose a Primary Facebook Email IDSelect a primary address that you want Facebook to use when it needs to contact you and that you can use to log on to the site. To do this, use the select buttons to select one of your email addresses. When you have finished making changes, click “Save Changes.” If you make a mistake, click “Cancel.”
Making a Facebook UsernameIn addition to choosing a primary email address, optionally, you can choose a username that’s associated with your account. This will be visible when people visit your profile, so make sure to choose one that you want associated with your account.
You must have a unique username; your username can only contain letters, numbers and periods; it must be at least five characters, and it can’t contain Web domain extensions such as “.com.” It generally shouldn’t impersonate someone else or be offensive.
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Use the Settings Menu to Set Your UsernameTo change your username or create one, click the menu icon in the top-right corner of the Facebook website. Then, click “Settings.”
Use the Username SubmenuFrom the Settings menu, click “General” to select the General tab; then click “Username.” Type the username you want into the input box. Facebook will tell you if it’s available or not. When you find one you like that’s available, click “Save Changes.”
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