To quote and add comment oneself on its journal

By the way, I’ve liked the quote feature on Discourse since I can pick a part of the target line.

By any chance, would it be possible for the function on one of my journal pages to add a comment or revise some sentences after posted it like the Discourse’s feature in the future?

p.s. Now, I can’t correct myself on my journal, can I? When my journal doesn’t have any corrections yet, I could only re-Edit it to correct myself or add comments, I think.