From the food they intake in different ways such as Plants or other animals such as insects which are their fuel
The abdominal cavity is the answer you are looking for.
Answer:
If you want to lose one kg of your weight, you need to create calorie deficit of 7,700. So if you want to lose one kg per week, you need to create approximately 1,000 calorie deficit every day. If you create 1,000 calorie deficit every day, you will lose one kg of your weight in seven-eight days
