Could i drink a glass of milk after ate pineapple? thanks

Yes: Yes, in fact milk and pineapple make a very tasty smoothie.

Milk and pineapple: I am not aware of any adverse "interaction" with that combination. If you have not been told to avoid these foods then ENJOY!

Yes: pineapple has digestive enzymes, but you want to digest the milk, so that isn't a problem. Pineapple can mess up some jello molds because it digests the jello and then it doesn't Jell. Oh.