Although it is hard to overeat while you are eating keto food, calories do matter.
No matter what diet we eat, we can never escape the fact that eating more calories than your body needs to maintain its weight will cause you to gain weight, and eating fewer calories than your body needs to maintain its weight will lead to weight loss. Whether you meet your goals or not depends on how often you are in a calorie deficit (eating fewer than the calories you need to maintain your weight) vs. a calorie surplus (eating more than maintenance calories).
Just because you are burning fat doesn’t mean you will always be burning your fat. Multiple pathways lead to fat storage, not just carb consumption and insulin (like many low carb diet proponents assert).
For a more in-depth look at calories and why they matter, click here.