Is it possible to become a neuroendocrine immunologist? i want to master the nervous, endocrine, and immune systems, and get a degree for that.

Long road: As a nonclinical specialist, you could earn several masters degree within neurobiology and immunology, or a PhD with a focus in immunologic neurobiology. As a clinical practioner, this is a much longer road involving obtaining a MD then specializing in internal medicine, then a fellowship in endocrine with a possible second neuroendorine fellowhip "and" then completing an immunology fellowship.