Most dog are lactose intolerant.
You can try giving milk in small quantity, if your dog doesn’t react to it, then it’s okay give it in small quantity.
Hope this helps
Dr. Anukarna Singh
Some dogs are lactose intolerant, for individuals who are milk can cause digestive issues like vomiting and diarrhoea. Dogs who aren't can have milk or milk based products freely. Some dogs who have dietary hypersensitivities are also known to be affected by milk intake, if your pet is digesting it well and not having any skin issues because of milk consumption you can give it.
Dr. Tajunnisa M
In addition to that, if you are feeding milk, it should be in diluted form.