How can we see new moon from the earth where it is night when it is on the opposite side of dark part of earth
understand that the Moon's phases are determined by its position in orbit relative to the Sun. The "shadow" is not cast by the Earth (a common misconception - this is actually a lunar eclipse), but by the moon's body itself.
It occurs when the Moon is on the opposite side of the Earth from the Sun and we see only the illuminated side. On that day it rises as the Sun is setting and sets and the Sun is rising. It is visible all night long.