If you own another email address, you can send mail as that address. For example:
- Your work, school, or business domain or alias, like @yourschool.edu or firstname.lastname@example.org
- Yahoo, Outlook, or other non-Gmail address
- Another Gmail address
Here are the steps.
Add an address you own
An email will be sent to the email specified under “another email address” to authorize these users to send emails.
Confirm the address
- Sign in to the account you added.
- Open the confirmation message you got from Gmail.
- Click the link.
Change the “From” address
After authorization, check that “Reply from the same address the message was sent to” is enabled:
The Google Support note on this topic can be found here: https://support.google.com/mail/answer/22370?hl=en