To create an automatic responder for your emails, open the Emails → domain name → Automatic Reply page. You will be able to create a new rule at the top of the page:
In the Email Auto Responders section, you can set up automatic responses to your emails, select specific times for when the automatic response should activate, or when the email should stop sending the automatic responses.
Auto-responders cannot be created for these email accounts:
If you want to know how to create Autoresponders for cPanel - check this article