Get the date – always prints date even if on second post on same day. $post_id is optional if inside of posts loop. See https://codex.wordpress.org/Formatting_Date_and_Time for $format value.

does not print date if displaying second post on same day in loop.

List current post categories with separator between each:

List current post custom taxonomies with separator between each:

List all categories as links to their own category page. See https://developer.wordpress.org/reference/functions/wp_list_categories/

Next/Previous Post Link. See https://codex.wordpress.org/Function_Reference/next_post_link also previous_post_link with same params.

Example: