What are you looking to do? I certainly wouldn't be telling you how much milk to drink as the decision depends on so many other factors - what else you're eating, whether you need particular (eg) vitamins, etc.
Personally I don't use milk at all. Too many carbs (lactose) for me - I use double cream for coffee though. I don't think I need any more D or A.
@MGConna I used cream in my coffee for many years, never used milk as my carb tolerance was so low. I kept to under 40 gm of carbs a day to control my HbA1c.
Now I am on Dapagliflozin and I need to have more carbs so I am drinking my coffee with milk - full cream, as I was not doing at all well for the first few days.
It is really easy to take in carbs from milk, so if you do not need them cream would be the best option. Vitamins D and A are in the cream.
Rich, creamy dairy can fit low carb - in some cases. Compare cheese, cream, yogurt and butter by net carbs, and see which to limit to break a weight stall.
www.dietdoctor.com
Diet doctor gives milk at 12g carb "per cup" which I assume is the US "cup" measure ie just over 0.4 pints.
For low carb/keto no milk or very little. Milk is high in carbs (lactose). For me it's none. I put double cream in my hot drinks (half the carbs of milk and twice as delicious). For calcium I eat lots of cheese which has the added bonus of being fermented. Some Greek yoghurt is fairly low carb, especially Fage.