In general, ignore the “Post format” option in this video. Add content or don’t.
And remember Google expects AT LEAST 300 words of content to believe what you say in a post or page has authority.
Also, be sure to add ONE AND ONLY ONE category to a post.
Use as many tags as you like.
Tags are like the index in a book
Categories are like the table of contents. Content is only shown in ONE place
Be VERY CAREFUL (as in don’t do it) in copying and pasting from an email .. You’ll get lots of extra code that is not necessary and which counts against you in search engine results.