Function Display article [closed]

If you only want The Content (of the main editor of the post) displayed, you can use echo get_the_content(the_ID). If you want more:

  1. First, you have to get the post data from the database, with the function get_post, or doing a query with WP_query.

  2. Then you can output different parts like title, date, content… accessing your variable properties, or doing a Loop, depending on what method you use.

I recommend you to examine other themes code to understand how it works, and of course The Codex, that is the WordPress documentation. The basics are very easy.