The same way you can see a torch from your phone in the middle of the day!
Light reflects off the moon. It’s bright enough that enough of the light photons don’t get lost in all the photons from the sun’s beams and reflections around the atmosphere. At night, there’s less photons to get lost in, so it’s just more likely that you can see the moon.
If you go to the middle of the countryside and away from all the streetlights, etc, you’ll see even more stars!
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