When you'll achieve your goal of becoming a successful doctor, you'll be dealing with or will be treating different patients. You need to focus on your work, don't hesitate when it will be your first time, in starting you'll be under training and then you'll become a professional doctor. Just be friendly be your patients. Deal with them in such a way that they don't feel , they are in a hospital. Deal with them calmly. First achieve your goal. It needs hardworking and when you'll become a doctor you'll automatically get to know what to do. You'll be given proper training before it.