Hi there!! From experience, I would definitely recommend studying the foundations of art first. Practice on those a few times, and go from there.
When you gain an understanding of foundations, it's like unlocking the secrets to complex treasures. Seeing how everything works, you begin to develop a natural sense of how parts of an illustration work together. As you practice it more, drawing will become more natural to you.
I also recommend using yourself as a reference! Artists are all unique and eventually develop ways to do their own shortcuts for establishing foundations. Observing yourself will help you develop your own shortcuts to drawing certain parts.
I wish you the best!