How do you get fly? Because i went looking in the Dep. store. And around how much would it cost o.o

It's gained by beating Zapmolcuno in the "NPC Fights." If you cannot beat the 3 Birds, trainers are always willing to teach your Pokemon "Fly" for a small fee.

go to npc fights -> zapmolcuno <-- beat them 3, after defeating Articuno, the pokemon will learn fly
Edit :
You need team of goletts/golurks to beat them. Also need toxic since this is will really help you decreasing their health faster. you'll need blizzard to defeating zapdos, bolt strike to defeating moltres and articuno.

You beat zapmolcuno. The pokemon that defeats articuno shall have it's moves replaced by fly. If the pokemon has toxic, toxic will remain and the other moves will be replaced. If toxic is replaced in means it glitched. That's all I know :P

How do you get golurk i had one but i losted it ?

You get golett/golurk from the random swap, or by using clan credits, you can choose to get a golett or a golurk. I believe there is a small chance of getting a shiny as well.