Looks difficult for a two-limbed creature to evolve the powered flight, specially the part of the blastoff, considering that pterosaurs had a quadrupedal blastoff which is good, but birds a bipedal blastoff which is more problematic or have less efficacy, so to have less limbs could be problematic
Also I just can think in not many real life species with just two limbs, one of them is the mole lizard, with just to strong short arms and long serpentine body.
I have to say, I know about flying snakes but there is a problem with the anatomy respect to expand the ribs to increase the gliding surface and have strong muscle attachments for powered flight, like a keel, the things look mutually excluyent. And that having long bodys increase the flight drag resistnace making to require more energy to fly
So, how a creature like this could evolve powered flight and what anatomical adaptations it need?
Remembering the parts of how would be the takeoff and stay in the air. And is necersary to use the two present limbs.