How can Gyarados be flying?
If that's so how can Gyarados fly? Is he like Rayquaza?
Gyarados is Flying to prevent it from being to overpowered. When Gyarados was first introduced in R/B, it was intended to be a Dragon type. But since a Water/ Dragon wouldn't have any weakness, it would be to powerful according to Game Freak (the only Dragon move in Gen 1 was Dragon Rage, dealing a fixed amount of damage). This, Gyarados was made a Flying despite not owning the gift of wings, feathers or rotor blades.
Well technically it was supposed to be a Water Dragon type but the only Dragon move in Gen I was Dragon Rage which did 40 HP to any opponent. The Flying part was a replacement so Gyara wouldn't be OP in that Gen. But yes it does fly the same way as Rayquaza. Oh BTW not all things need wings to fly xP