If i got attacked and can't defence , i am forced to draw two cards. If the first card that i draw is an attack also, i can immediately play it so i won't draw my second card OR i must draw the 2 cards first because i coyldnt defense the attack????
Can you point out where it says you draw two cards? Despite the resemblance, this is NOT UNO.
You take TWO TURNS, which means you get to do everything you normally would in a turn, ie, playing as many cards as you want. If you happen to play an attack card in your first turn, you end your turn and don't have to take a second. If you don't, then you end your first turn like normal (which involves drawing a card), and then take your second turn. If you play an attack card in your second turn, you treat it as if you played an attack card, which means your turn ends without drawing.
This is right in the rules. These rules are really easy to understand. Read them.
Here's a link: http://explodingkittens.com/how