What makes that question interesting is that it presumes there is some reason you couldn’t.
The moon is just as much out in daytime as it is at night.
In the daytime, the sun is so much brighter than everything else that the moon may not be noticeable even when it is visible.
At night, however, it is the brightest thing in the sky.
As the moon orbits around the earth over the month, it is in all parts of the sky over a twenty-four-hour period.
How much of it is visible depends on the phase, or how much of it is illuminated by the sun at a particular time.
The daytime sky is bright because the atmosphere scatters sunlight, but the moon is close enough and large enough to reflect enough sunlight so that it is brighter than the surrounding sky.
That is not true of the stars.
However, an astronaut on the moon can see stars even when the sun is out, because the moon has no atmosphere to scatter the sunlight and make the daytime sky bright.