How to register a new page template in WordPress?

Question

PHP

I have a site. A .swf file is attached to each post (the file address is set in an arbitrary field). I want to make a page on which these .swf applications will run.

The essence of the question is:
How to create such a page?

For example single.php
Referring to the addresses site.com/?p=17 , site.com/?p=36 , site.com/?p=741 , takes the required post from the database and displays it at the appropriate address (if using CNC)

I want to make an analogy of play.php to address site.com/play/?p=17 , site.com/play/?p=36 , site.com/play/?p=741the page also pulled all the information from the database. (I know how to issue the output directly) and displayed the URL of the page in the given format:
For example, the post address: site.com/post-name.html
and the launch page was at site.com/play/post-name.html