Hi Chris,

For the icon in the top left, see How do I add Social Media Buttons below the Logo?

For the Comment Count next to the Write a Comment button, that only shows up when there are at least 10 comments.

For the Author Name and the Category Name to appear in the post meta, you need to enable Multi-Author Mode in Dashboard → Appearance → Customize → General Options.

For the “in [CATEGORY]” at the top of the post, that only appears when the browser window is resized to a smaller size, or when you have Single-Column Mode enabled (see Dashboard → Appearance → Customize → Layout Options).