How do I set up a SMTP email address?

You can then navigate to the new Settings > WP Mail SMTP tab in your dashboard, where you can set the email address your SMTP server will use to send messages from. If you leave this setting blank, the plugin will use wordpress@yourdomain.com as the default: After that, you can choose the name that will be used as the sender for your emails.
For More Information Please Refer:
https://www.a2hosting.com/blog/wordpress-smtp-server/
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