What type of doctor treats adrenal deficiency or adrenal fatigue? And do all drs believe that its an actual condition?

No - such - thing. "Adrenal fatigue" is a nonexistent condition that "holistic" doctors trot out to describe common symptoms that many people have who are depressed, anxious, stressed, etc. Those whom the quacks diagnose with this usually have NO problem whatsoever with their adrenal gland function, despite whatever bogus non-approved test is done (typically a saliva cortisol test) that is supposedly "abnormal."