I don't track anything, but when I first started keto (carnivore now) I was tracking carbs.

To my mind, if you want to burn body fat the big idea to keep in mind is that your body basically burns either fat or carbs but not both at once (and drinking alcohol is also a carbohydrate).

This is the basic reason people find success with keto or carnivore. It's also the basic reason people find success on low-fat diets (they burn sugar during the day and body fat while fasting between dinner and breakfast).