Magento has dozens of built in email templates which can be customized and used for your store. The directions below will take you through the editing steps.
Go to Marketing > Email Templates.
Select "Add New Template" on the far right of the screen.
From the Template Dropdown, select which template you'd like to edit.
After picking your template, click "Load Template".
Edit the template as needed. Be careful not to remove any code you see in the template! You can also preview your work as you go; simply click the "preview template" button.
Be sure to name your template BEFORE you save it!
Your new template will now show in the list of templates under Email Templates.
Once you're happy with your new template, you'll need to update the settings associated with this email.Directly above the "Template Name" you'll see exactly where this email is used for. Be sure to navigate to that spot to update the template in use to your new template.
The logo used in the Transactional emails can be updated in:
Content > Design > Configuration
Please check with Support or your Project Manager about which record should be updated.
Once in the template; select "Transactional Emails".
Upload your preferred logo in the appropriate field. Be sure to updated the Logo Image Alt field as well!
"Save Configuration" when done!