Furthermore is used to introduce a new idea that hasn’t already been made. Even if that idea is closely related to a previous one, if it’s still a new idea, “furthermore” is the correct word to use. “Furthermore” is used at the start of a sentence because you’re putting a new idea forward.

Addition transitions help introduce new ideas that build upon what was previously said. Example: “The project was a success. Furthermore, it opened doors for future collaboration.” Example: “He’s an excellent athlete. Moreover, his academic record is outstanding.”

When you use a transitional phrase, you let the reader know that there is either more to come on the subject or a take-away on the subject. Furthermore, it tells the reader there is more to come on the subject – even if only one sentence.