Some writers find story structure restricting. Whether it's a three act structure, the Hero’s Journey, or any number of narrative frameworks. One could argue that it produces repetitive unoriginal works.
But look at the human body. Generally, we all have two arms, two legs, a torso, head. Yet, look at the diversity among all of humanity. Would you say we're all the same? A frame work is just that. A frame. It give your story structure, or rather, it prevents it from being an amorphous blob. If you can't find a way to tell your story within a framework, maybe you don't have a story.
Horse Master Studies from THE ART OF ANIMAL DRAWING by Ken Hultgren
One of the best ways to learn is to draw from someone who has mastered drawing it already.
Observation is THE best way to learn, but master studies support your observational drawings, because someone has decided for you, what to leave out, what to accentuate or downplay.
These are decisions that you will HAVE to make as an artist. The hard part for beginners is that you're still developing the artistic knowledge to know what is a good or bad decision.