All B-boys are handstand masters. Start training them now!
Alot of the moves are based off of handstands, 1990s, 2000s, airflares hand hops etcetera. There is no trick to handstands, with a little practice you can get them in a month, its about 50/50 strength and balance. If you practice against a wall you will get them fast. This is how I trained for them, similar to gymnastics.
Once you master them, you can do stuff like this.
The answer to most of your handstand questions is to practice more!