These comments you gave were very useful, so thanks everyone for them! So if i still want to go there, I should be sure for that i'll have a job as soon as i arrive. Or thats also good to go by a visit visa, and if i cant find anything then coming back.
About working: I trust myself, i'm not lazy and im hardworking. I used to work in factory, fastfood restaurant, even on a corn-field in the middle of summer 8hours a day. [i can't imagine worse:)]
About being a cabin crew: that's exactly what i wanted to be, but i checked many sites, many airlines but unfortunately they're not looking for girls under 20, or mostly 21.
I think i will try to talk to girls who already work in Doha as waitresses and these kind of works.