Generate a reel for it first and it becomes a permanent link you keep. Sign up and your writing follows you between documents and devices.
The link opens your reel — the replay of this document being written, start to finish.
copies the reel link on its own.
copies your document text with the reel link appended, ready to paste into an email — as rich text where the destination accepts it, so the link is clickable.
opens a new email in your mail app with the same text and reel link already in it.