Can anyone help me overcome my fear of public transportation?

Some ways. Systematic desensitization and invivo exposure. You will need an experienced therapist who you trust and who can help you go through the procedures step by step.
CBT for some works. In contrast to other forms of psychotherapy, cognitive therapy is usually more focused on the present, more time-limited, and more problem-solving oriented. In addition, patients learn specific skills that they can use for the rest of their lives. These skills involve identifying distorted thinking, modifying beliefs, relating to others in different ways, and changing behaviors.