Well, you did say wind training.

Rasengan would be ninjutsu. If you've learned the basic one, then I can teach the others. I don't teach basic ninjutsu so I can't teach you the normal Rasengan.
Well, Wind Stream is used generally to change direction while in battle. Now, I've never used it so I can't say how effective it is nor can I tell you if you can use for more than one direction, like using it in an arc. What I can tell you is if you point it at the ground when using it, it can blow up a dust cloud, enough to conceal your location if your opponent doesn't have a sensing ability.
To use it, first gather wind chakra in your lungs.