The following lesson is a mere introduction/revision to the anatomy of the spinal cord. Consult your teacher regarding the full information.
The spinal cord itself is rather short, its length is approximately 45cm in adults; starting from the end of the medulla oblongata at the foramen magnum, reaching the T12-L2 spinal vertebrae.
How do spinal nerves reach the lower part of the body?

The lower portion of the spine and spinal cord -- Copyright © Meddists.com