Where do human get the stuff they need to survive?

Humans survive through gaining nutrients by eating

We must have food, water, air, and shelter to survive. If any one of these basic needs is not met, then humans cannot survive.  Oxygen is one of the most essential human needs. Our bodies need a consistent supply of it to function properly. Without access to oxygen, you can experience a condition known as cerebral hypoxia, which affects the brain. As little as five minutes without air can result in brain damage. We get food from plants and animals, we get water from rivers and streams, and we get shelter from building anything that is around.

Explanation:

the body's situation won't change the forces are equal opposit and on the same body