- I would say "Add the text of the message" or "Add the text of the message to the message body" or "Add text to the body of the message" rather than "Enter the message body," which threw me off for a minute.

- Decapitate "Component" in "HTML Component."

- "The same options" sentence is a little awkward; how about "The email message editor has the same formatting options as the HTML component editor in Studio"?