By default, Grav's Email plugin use PHP Mailer to send email. To switch from PHP Mailer to SMTP to send emails is pretty simple. You can do this right in Email plugin's setting.

Access Grav administration area's link and login, click on "Plugin" from the left menu.

Click on "Email" plugin to open its configuration page.

You will see have the following options to configure the plugin:

• Mail Engine: Choose "SMTP".
• Content type: Choose "HTML".
• Email from: Enter your name or your business name.
• Email from name: Enter your email address or your business email address.
• Email to: Enter your name or your business name.
• Email to name: Enter your email address or your business email address.
• Path to sendmail: You can leave this field.
• Debug: Set to "Disabled".

For the following options:

• SMTP server
• SMTP port
• SMTP encryption
• SMTP login name
• SMTP password

You enter the values of your SMTP server.

Click on the "Save" button at the top right corner of the page to save and apply the new configuration. Now you can try to send email from your Grav site, for example using your contact form to send email to your site, if email is not sent to your inbox, you may need to adjust your SMTP server's information.