one: in how many time do you learn to do double flips on floor and on the uneven bars? two: Soon i will get into gymnastics so do you think that i can a layout dismount on the uneven bars?

How long it takes to learn double flips on floor and uneven bars depends - it's different for everyone. Usually first you learn tuck flips, then layout, then you double it. Tuck front and back are in level 6, flyaway (back tuck on bars) is level 6 too, you can do a layout flyaway in level 6 too. If your swings are good on bars, and you have a good experienced coach, maybe you can even learn a flyaway with spot on your first lesson. And flips into the pit if you have one. Double flips are in the optional levels, like levels 8,9,10, elite, but you can work on them before that too.

Some people learn layout flyaway on bars first to get the get away from the bar motion, not pull the bar, etc.; tucking is good if you need to get more rotation. Depends on the coach.

thanks for the Info!