Psychotherapy is a mental health profession. It can be delivered to individuals, couples, families, or small groups. The goal of psychotherapy is to help clients improve their emotional and mental health.
Psychotherapy can help people by teaching them skills that they need to manage their symptoms. They do not need to have a diagnosis in order for psychotherapy to help them with their symptoms.
If you are thinking about seeing a therapist, it may help you to read up on how therapy works so you know what is expected of you and what it will be like when sitting down with your therapist for the first time.