Mental Health Care Professional
Dallas/Fort Worth Area
Since I am a psychologist I can only give you some general information. Psychiatrists are medical doctors who specialize in treating patients with mental health problems. They graduate from medical school and then complete a residency in psychiatry, usually three years in length. As an undergraduate you would probably want to major in premed, which does require a good deal of chemistry and biology.
I also want to mention that psychiatrists today rarely do "talk therapy" and treat their patients almost exclusively with medication. If you are interested in counseling people this is probably not a good career choice for you.
Good luck in your educational and career pursuits.
Ray Finn, Ph.D.