When I'm putting in my keywords in the appropriate field, do those words have to be in the copy of the article you're writing? What am I supposed to do here?
Yeah you can put the keyword that are not in the blog post but please make sure the keyword has in the description as well
If your keywords at least semantically related - put them in, they will not hurt you but if these keywords are not related, don't add them. They will not do you any good.