I looked it up on Amazon, and it looks like each serving (which is 4 times a day) is about 20 calories, and 5 grams of carbs.
Technically, this breaks a fast since it does have calories, but for just weight loss purposes, I don’t think that it would make much difference in fat loss.
I see it says that you can add snacks and fruit juices, and if you do that, then it would definitely be breaking the fast; but any servings that you have with your OMAD meal, you can add fruit or juice because you are eating anyway. Otherwise, you would have it just with water.