Can birds fly?

Not necessarily. For example, chickens are birds, so they are not good at Yu Feixiang.

Other most typical flightless birds, such as: African ostrich, penguin, emu, big Rhea, crane ostrich, kakapo, Peru's Grebes, white-headed boat duck, short-winged boat duck, kiwi, egret crane, Guam crake and so on.