Here is a definition of a neurosurgeon - A neurosurgeon is trained in the diagnosis and treatment of disorders of the brain, spine, spinal cord, nerves, intracranial, and intraspinal vasculature. A neurosurgeon may complete additional training with a Spine Fellowship and specialize in spine surgery (from: https://www.spine-health.com/glossary/neurosurgeon)
There is also a specialty called neurology, defined as: Neurologists are highly trained clinicians capable of diagnosing complex conditions through detailed history and physical examination, including testing of mental status, vision, speech, strength, sensation, coordination, reflexes, and gait. Even as medicine becomes more dependent on technology, the neurological exam will remain a critical component of the patient evaluation

A trained doctor may do both diagnosis and surgery, or just one of the two.

Perhaps you meant an orthopedic surgeon concentrates on bones?
Sue