It is so great that you are being proactive in taking steps to make your dreams come true! To answer this question, I think I may need just a bit more clarity. What is it you'd like to do on YouTube? Do you want to have your own channel, and, if so, what type of material would you like to publish? If you are looking to be a comedian, acting classes might be valuable. If you are looking to be a technology product reviewer, it might be helpful to take some classes in journalism or marketing.
There is something to be said about taking courses in a breadth of fundamental subjects (i.e., mathematics, literature, history, philosophy, natural sciences, social sciences, etc.) prior to/in addition to more specific courses that focus on building technical skills. Such courses help to increase intellectual ability more broadly and act as a foundation for future learning (see https://www.topuniversities.com/blog/what-liberal-arts-education).