if i got a male shinx with a female picahu holding light ball give me a pichu with volt tackle or would it have to be picachu and picachu with light ball?
No, only male pokemon can pass down moves, but if Shinx could learn Volt Tackle, which it can't, thats how you pass down moves.
However, if you breed Pikachu holding a light ball, and Ditto, thats how you can get a Pichu with Volt Tackle. HTH!
Get a female Pikachu with a Light Ball, get a male pokemon in the same egg group, leave them at the daycare, get the egg, hatch it, and you should have a Pichu with Volt Tackle.
Source: Personal Experience
P.S. Volt Tackle is really useful. monitor your HP when using it so you don't act like a suicide bomber or commit suicide.