AEM has built-in support for sending email notifications as part of workflows.
This feature is called "Workflow Email Notification" and is available out-of-the-box.
To use this feature, you will need to configure the SMTP server settings for your AEM instance and set up the email notification step in your workflow.
You can also use the "Email" step in the "Communication" category of AEM Workflow Steps to send an email at any point in your workflow. You can configure the recipient, subject, and body of the email using workflow variables.
You can also use the "Email" step to attach assets to the email.
In addition, you may also use the AEM's built-in Mail Service to send the email.
Reference: https://experienceleague.adobe.com/docs/experience-manager-64/administering/operations/notification....
AEM also provide a feature called "WorkflowLauncher" which triggers the workflow on certain events like page publish, you can use this feature to trigger the email notification upon page publish.
