I have many versions released so far for an App (without In-App purchase).
Do I have to submit anything to be able to test In-App purchase?
What do I have to do?
I’ve implemented this – http://troybrant.net/blog/2010/01/in-app-purchases-a-full-walkthrough/ – so far, nothing happens when hit Product Details, or Purchase.
You don’t need to submit and reject a binary in order to advance your development process or test In-App Purchase. The link you’re referring to, although helpful, is now out of date and the quirks in iTunes Connect that it refers to are gone, so don’t follow it blindly!
The Apple doc is much more reliable and I recommend you use it instead. I actually wish I had started with the Apple docs rather than the link you provided when I implemented In-App Purchase in my app a few months ago–I can’t recall the details but I do remember that it led me astray, particularly regarding the need to submit and reject a binary.