Why is the moon not visible from Earth on a new moon?

The moon at this time is on the same side of the earth as the sun, and therefore the dark half of the moon ball, not illuminated by the sun, is facing us.
In this position of the Earth, Moon and Sun for the inhabitants of the Earth, a solar eclipse can occur. It does not happen every new moon, since the moon usually passes in this phase above or below the disk of the sun.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.