How many tectonic plates does Earth have?

Jan 14, 2023
If all above water continental plates broke apart ~250Mya what caused it?
Are we sure the moon didn't form ~250Mya?

I imagine an astroidal impact in the Pacific plate caused the continental plates to break apart and I imagine that astroid became the moon b/c the moon ~1.2% the mass of the Earth with a diameter ~¼ that of Earth's; moon is small.