Knowing where to go when you want to become a self-taught artist isn’t easy. Some people choose to base all their knowledge on one artist or one course. I recommend though to look up several artists. Learn to see things in different perspectives, and see what fits you best at that time.
There are many amazing artists out there, and some of them use YouTube as a platform to teach. So, if you are looking to learn something new, or want to understand different approaches to the same subject a bit better? These artists are a great place to start. They will help you getting a better understanding of the work field, different techniques and approaches, and different materials and tools.