Notice the yellow highlighted section. If you uncheck the box above it, you will not have an automated display of author posts at the bottom of every post. It gives you a small bit of code to add to your post to have it done just for an individual post. It's just an option, but I'd recommend leaving the box checked so your site is uniform throughout and visitors know that they can get more posts by an author anytime they view one post.
The other setup options are self-explanatory. You can decide what the title text will be of this section, as well as how many previous posts to display.