When deciding on career coaching as an occupation I took a lot of time to research and gain experience. One of the best tips I have ever received was to talk with a professional in the field that you are interested in. An informational interview will help you to decide if you like the occupation or if there is more that you have learned that may not be a great fit. This also opens the doors for a professional mentoring relationship as well as a possible internship in the future if the professional has that capability at their company. Here is a great website that explains more: https://www.livecareer.com/quintessential/informational-interviewing.
I finally realized my passion was in career coaching after volunteering in the Career Center at my university and doing 4 internships within the field. These experiences ultimately helped me to gain my first post-graduation professional position as well. Remember that professionals are people who have been in your shoes. They love to help and give advice. Think of the career journey as an exciting time when you can explore multiple options. You do not need to know exactly what you are going to do when you graduate high school or even when in college. It takes time and that is completely fine. As long as you are gaining experience and connecting with others you will be just fine!