A psychologist is not a medical doctor but is trained in helping clients with mental health conditions. Psychologists cannot prescribe medication—except in Idaho, Illinois, Iowa, Louisiana, and New Mexico—but can diagnose issues like depression, anxiety, or phobias and provide talk therapy, Cognitive Behavioral Therapy (CBT), or other treatments.
A psychiatrist is a medical doctor who is authorized to prescribe medication. While psychiatrists will diagnose your condition and determine the proper treatment plan, they typically don't offer talk therapy and will refer you to a psychologist for those services instead.