Thanks for asking.
You can visit our Knowledge Base index page to find out the tutorials. We do have interactive tutorials for modules like Header and Footer builder, Cornerstone builder etc. However I do agree that finding out videos and KB navigation is a bit tedious process as of now. We are aware of the problem that our customers are facing. As of now I am not in the position to share the ETA but we are in the process of redesigning our KB section. It will have a much more user friendly navigation system. We are also coming up with more tutorials including videos to explain the concepts. For latest product announcements I suggest you to please keep an eye on the changelog page.
For now I request you to please take a look at the tutorials to get started.