How many constellations are there in astronomy? What are their names? When can we observe them?

Andromeda, Pump, Orchid, Aquarius, Eagle, Aquarius, Aries, Auriga, Shepherd, Carver, Leopard, Cancer, Dog, Petunia, Capricorn, Carina, Centauri, Cepheus and Erigeron. Gemini, Crane, Five Immortals, Clock, Ophiuchus, Hydra, Indian, Boutos, Leo, Little Lion, Rabbit, Libra, Wolf, Tmall, Lyra, Mountain, Microscope, Unicorn, Fly, Rectangle, Antarctic and Ophiuchus. Shield, snake, sextant, Taurus, telescope, triangle, south triangle, azalea, Ursa major, Ursa minor, canvas, Virgo, flying fish, fox.

As for observation, it is also related to latitude.