Hm, I'm not sure if you're in the field of psychiatry, or psychology, or even anything remotely related to that, but for instance, can a psychiatrist perform any kind of therapy?
As a med student, I'm required to take a rotation in psychiatry. My school's rotation in psych was for 6 weeks. It was incredibly fascinating and memorable!
There are many types of therapy, many of which require proper training before any professional can execute them. A psychiatrist can choose to learn various types of therapy like CBT (cognitive behavioral therapy). However, their training focuses primarily on understanding the medical assessment and management of psychiatric illness and medication: diagnosing psychiatric illness, the signs and symptoms of psychiatric illness, recognizing/monitoring effects and side-effects of medications, and recommending what they believe are best therapies for their patients. Therefore, while a psychiatrist can recommend a particular type of therapy for a patient, that psychiatrist himself/herself may not have been trained to administer said therapy and may recommend a psychologist who is trained.