I took training on NAV 2009, completed a project. Now, when I am looking to develop on NAV 2016, I am facing difficulties about this "Role Center" thing.
Thanks & Regards
Well try to start on Youtube, there you'll find a lot of great example on almost everything in NAV.
Specifically about the changes between the old classic versions and the RTC versions, then that was basically covered with version 2009.
But youtube have lots more there. If you're more traditional, then go to Amazon, they also have tons of books on learning NAV.