Cats can drink lactose-free milk, but there are a few things to keep in mind:

Individual differences: Not all cats are suitable for drinking lactose-free milk. Some cats may be allergic or intolerant to the proteins or other components in milk.
Give in moderation: Do not overfeed lactose-free milk to avoid indigestion or other problems.
Alternative: It's best to provide pet milk or water specifically designed for cats.
Observe the reaction: After feeding the cat with lactose-free milk, observe whether there are any adverse reactions, such as vomiting or diarrhea.
Nutritional needs: The main source of nutrition for cats should be high-quality cat food.
Special circumstances: If the cat has specific health problems or dietary restrictions, dietary arrangements should be made under the guidance of a veterinarian.