I am confused can someone please explained to me about this service?
If you want distribution (Amazon, etc. ) you need a special international number called the ISBN. You can buy one yourself via myidentifiers.com or you can get one from lulu for free (they will be listed as publisher ) or you can buy one from lulu and have yourself listed as publisher.
Just start a project and get a feel for the process. Or, you can also Google ISBN information.