Before you create your email template, please ensure that your email settings have been established first: Sending Emails from Donorfy
Creating an Email Template
From Settings > Configuration > Acknowledgements & Documents you can create your email templates.
The From Email Address will need to be from the email specified in the Email Server Settings, and the From Name (what the receiver will see in their inbox) can be whatever you want it to be displayed as.
It is advisable that you set your Description to include Email in so it is easily distinguishable from your letters.
You can also set an Activity Type of Email Outbound
The email text editor works in the same way as the one for letters, you can find the details for placeholders, etc here: Setting up One Off Letters and Emails