Veritasium’s Derek Muller asks and answers: How Far Away is the Moon? (The Scale of the Universe)
It takes the moon about 27 days to orbit the Earth. What makes it go round? It is the gravitational attraction of the Earth on the moon. Due to the moon’s velocity, the Earth keeps pulling the moon towards it without the moon actually getting closer to the Earth. This is similar to how satellites orbit the Earth.
And related watching: Why Does the Moon Orbit the Earth?