apart from human, how many animals can walk by only-two legs standing position?

Answer 1

All the birds

Answer 2

They are called bipedal animals
Humans, birds and (occasionally) apes walk bipedally. Humans, birds, many lizards and (at their highest speeds) cockroaches run bipedally. Kangaroos, some rodents and many birds hop bipedally, and jerboas and crows use a skipping gait. Chimpanzees walk with their knees bent and their backs sloping forward. Most birds walk and run with their backs and femurs sloping at small angles to the horizontal, and with their knees bent. These differences from humans make meaningful comparisons of stride length, duty factor, etc., difficult, even with the aid of dimensionless parameters that would take account of size differences, if dynamic similarity were preserved. Lizards and cockroaches use wide trackways. Humans exert a two-peaked pattern of force on the ground when walking, and an essentially single-peaked pattern when running. The patterns of force exerted by apes and birds are never as markedly two-peaked as in fast human walking. Comparisons with quadrupedal mammals of the same body mass show that human walking is relatively economical of metabolic energy, and human running is expensive. Bipedal locomotion is remarkably economical for wading birds, and expensive for geese and penguins.

Answer 3

Most species of birds can walk on two legs, there are a few lizards (such as the fringe-toed lizard, and basilisk) that can run on two legs, and many of the primates can walk on two legs (but not very efficiently). So there must be thousands of animals that can walk on two legs.

Answer 4

Bears and primates can walk on two legs, but only for a small while.