Can i get a specific author in main menu and when you click on it to see all the post buy this author. Also i need to see all posts ordered by authors too in the menu. In what template should it build, because it is not a category.
By default, you can view posts by authors with a URL of the form
If you'll be writing any PHP and need to output a link to an author's posts, see the function get_author_posts_url.
Edit: If you'll be writing your own author post page template, the filename should be one of the following formats:
author.php. The templates override in the order I listed them -- last one being the fallback.