In this documentation you will learn
Email Template is a shape of email while system sending an email such as sending order email.
In this admin section, admin user is able to edit / view an email template
How to add new email templates
In this admin section, while admin user is able to edit an email template but it's not able to add or delete an template because email templates is being sent by using code so it is mostly a developing issue, plugin or manual adding make it more reasonable.