can an astronaut on the moon use a straw to drink from a normal glass?

Yes, as long as he's inside the landing craft. Otherwise no because his helmet would prevent him from putting the straw in his mouth.

Well he could but it would be really cold, and even if he somehow did it without causing a leak in his helmet, as soon as he finished the drink or lifted the straw out of the drink the vacuum would literally rip out the straw and the majority of his face and body through the straw-sized whole in his helmet, killing him instantly.  So, no, you really should not be drinking from objects outside your helmet when on the moon if you don't want to be killed by explosive decompression (vacuum).

Suction does not depend on earth-normal gravity to work. Assuming his mouth is accessible (no helmet) and there's beverage in the glass or sealed juice box, yeah, he totally sucks.

External pressure is needed to drive the liquid up the straw.
If the liquid is in a pressurized chamber; he could.
If it is in vacuum he could not.
A juice box could serve as a pressurized chamber.
If the astronaut is exposed to vacuum he will die of course.

He will only be able to drink inside the landing craft. In that case, it would be just like on Earth, perhaps a tiny bit easier due to lower Moon gravity. The partial vaccuum to suck up the juice is created by the muscles of his oral cavity so it would work just fine on the Moon to lift the juice out of glass or box.
There is absolutely no way this can be done outside. For one, due to no atmospheric pressure, the juice would boil and evaporate quickly and part of it might freeze in the end (kind of depends whether you are in the sun or not as the temperature differences are enormous).

lol