Create a Page Template that displays Only One Page Menu Item

I want to create a Page Template that displays only one of the pages from my Page Menu.
I also don't want any header image or blog title or any category menu to show.
Just want the one page parent menu with it's drop down children pages.

I know this can be done, but don't know how to call up only this item and suppress everything else.
So there would be nothing at the top of the page except this drop down page menu and its page contents.

I know how to set up a basic Page Template.

It would look something like this:



Thanks.