Look for two points when choosing.
First: the nose should be pink and the beak slightly black. This young bird is usually 3-4 months old. If the nose is white and the beak is black, it is an old bird. It's best not to buy it.
Second: the fur should be smooth, the eyes should be big and round, and the bigger the better (just look good). Birds are energetic and love to call, so that they can be healthy.
As for the difference between men and women.
Female bird white (albinism): The inside of the flight feathers of adults and young birds are all yellow spots except the innermost two.
Male birds are white (albino): young birds, like females, have spots on their wings.
The male bird is white (albino): there are yellow spots on the inside of the middle bird's wings, but there are no yellow spots on the inside of its new flight feathers (mainly see the new flight feathers here).
Male bird white (albino): There are no yellow spots on the inside of adult bird wings.
I will send the picture to my space later, you can have a look!