Webbed wings- they're just hands, the claw on the wing is the thumb, the 'prongs' are the fingers.

Wings in general- wing to body ratio is important, you want your wings to be about the length of the body, usually including tail unless the creature has an especially long tail. If you look at birds, their wing to body ratio is generally beak tip to tail tip

If you can't achieve that wing to body ratio because of a small canvas, just make them as long as possible.

Folded wings- I don't draw folded often, but even when folded, wings are quite large, and on a dragon, the wingtips will often poke out the back.

By folded I mean tucked to the side

I hope this helped!