To create an email template, you can follow the steps below:
Select Marketing from the left side menu
Select the Email Templates option
Click the Add New Template button
On the new Email Template screen, you will want to select the email Key from the Key drop down menu. This will then populate the available tokens that you can add to the email which will merge in the actual values based on the customer and/or order details.
Once you have added your content (Name, Sender Email, Subject and Content), ensure the Status field is set to Enabled