What does the body use calories for?

Your body needs calories just to operate — to keep your heart beating and your lungs breathing. As a kid, your body also needs calories and nutrients from a variety of foods to grow and develop. And you burn off some calories without even thinking about it — by walking your dog or making your bed.

Explanation:

to keep your heart beating and your lungs breathing.

Explanation:

because health skills are tools and strategies and also practical skills are also something you need to learn (like tools and strategies) and put it in reality.