Like in the E3 video in bleak falls barrow when he kills the draghur?

Which school is this spell and does anyone know where i can buy it?

Also recently i obtained the perk to dual weild destruction spells however when i cast them, the spells just look normal as they would if i had cast them without the perk, the hand positions are also the same as before, have i done this wrong of something?

You scream at the guy to stop moving so fast. Litterally. It's a shout.

It's a dragon shout. Go do some main quests. Oh and make sure you're casting the same spell, like fireball + fireball, not flames + fireball, or frost with fire