So I got my new graphic card that I bought 3 month ago

This one :
https://www.amazon.fr/Gigabyte-N960W...2332881&sr=1-1

But I didnt knew you need to cable the card with the power supply since it wasnt specified.

I need to buy a fitting power supply for my graphic card in no time (by the end of the week)
On that website there is a list of avaible power supply . What should I buy to make it work with my GC ? Since it have 2x6 spot on it.
http://www.pcgamer.ma/161-boites-d-alimentation

I really have limited time, also I know my computer need less than 500w but I have No idea how power supply work since its my first time ever with it. Thanks to anyone that got some knowledge and can help me out.