Single Post Template

I want it so that when I create a post–I select from the drop down list which page I would like it to appear on. I am relatively new to WP and am struggling to find some adequate instructions on this process, although diligently searching. From what I understand, you have to create a new post template by copying/renaming the single.php file. (Am I correct?) Then you have to find some language to the affect of:

<?php
/*
Template Name Posts:
*/
?>

and replace with the new name.

Nowhere in my single.php file is there any mention of a template name post. So, what exactly should I be looking for????????? My single.php is as follows: Does anyone see where I should put coding?

[Code moderated as per the Forum Rules. Please use the pastebin]

Why is this information so difficult to figure out. There are a lot of posts/topics, but no real sufficient adequate all encompassing answers . . . please help!!!