BeBuilder Blocks vs BeBuilder
BeBuilder Blocks and BeBuilder are the same tool. Whatever you create in one is reflected in the other. It's like having 2 builders in 1.
BeBuilder Blocks is a typical backend wireframe editor that allows you to build content easily and quickly using Sections, Wraps and Elements. Design whatever you like and then preview your workflow without page update. Moreover, you can customize your backend editor by using included settings. Decide if you want to have simply view where the content from elements does not appear, on/off hover on elements or fill items with sample content.
BeBuilder is a completely different content management concept from the one known from the backend editor. You can see your layout exactly as you built it. Furthermore, directly from Live Builder you have access to Page Options so there is no need to switch between the dashboard and editor. Also, you can preview the layout you work on mobile devices and make changes if necessary. This will significantly speed up your work.
In summary, it is one and the same tool but with two different ways of working. Choose your own path and build exactly the way you like.