Adding new sections to an OpenCart page is not the easiest thing to do, but there are some great walk-throughs which make it easier. I followed Jamie Taylor's tutorial (Adding Positions to OpenCart 18.104.22.168 Theme) on HTMYELL.
However, his syntax use changes when giving example code for the
/catalog/controller/common/content_middle.php file. He suddenly starts using the name ‘home-one when previously he was using ‘content-middle’.
Stack Overflow also has a good example, but slightly less generic and the section doesn't get added to the admin GUI.