The calendar shows that the new moon occurred about 21 days ago. what phase is the moon in right now?

The answer is the Last Quarter.

A week after a new moon, the first quarter occurs. Another week after the first quarter, the moon's phase enters full moon. On the third week from the new moon is Last Quarter. In this phase, the moon is three-quarters around its orbit on Earth. And in the next week, the moon enters a new cycle and the moon's phase is back to new moon.