Yeah, it’s almost impossible to use a tablet in Blender with RMB select. The stupid problem here is that painting and sculpting need LMB select. This really needs to be fixed up in a much better way.
The biggest issue that still remains is zooming and general scroll button usage (my stylus has no scroll functionality). I was going to see if mapping one of the tablet buttons to MMB would help but my tablet drivers are kaput.
Yep, it’s just about essential to have the tablet driver set up for 3 button usage. I have LMB = tip, RMB = lower switch, MMB = upper switch. Life will be quite difficult without that.
As for zooming, I’ve also been experimenting at work with a new way of zooming, which I’ve stolen from Fusion, a compositing app I’ve been using lately. Basically, MMB pans/rotates, and MMB+LMB zooms. This works extremely nicely with a tablet since it means you can just hold the MMB switch to rotate, and then press down on the surface to zoom. It lets you have two different operations with just one hand, which is much nicer than having to press Shift or Ctrl, and it feels very gestural. I need to finish up getting this working, I’m just busy 
I have seen on the internet how the professionals uses a tablet to add/make special effects to their movie. How and what do they do? And Why I a tablet better than a mouse to do that?
A tablet is just like a mouse, you move the pen over the surface to control the mouse pointer, and press down to click, so the people you’re imagining are just using any kind of software app, but controlling it with a different input device. There are quite a few advantages to using a tablet, some of the main ones are: it puts less strain on your fingers than a mouse, it’s a lot easier for tasks like painting, drawing or sculpting (especially if you have experience drawing in traditional media), and most tablets have pressure sensitivity, where you can do things like vary the intensity or size of a paint stroke based on how hard you’re pressing against the surface.