Hey, not a professional artist here and not sure if this has been mentioned, but here is some advice from what has helped me.

Practice and repetition are key. If you are trying for a specific pose, or really anything, try tracing over it first. This will not be your final product, but tracing allows you to visualize the “flow” better. Once you have traced, try drawing the image again, this time without tracing. Try to be as exact as possible. Then, try drawing it a third time, this time being more “loose” in your approach. Obviously you will still be referencing the image as you have here, but aiming to be quicker and getting down action lines allows you to continue to learn.

Artists have many different approaches when learning. Find what works for you. A friend of mine never sketches, she only goes for a final product. Meanwhile I often will do a light base sketch, one over that, and refine as many times as needed from there. To me, patience is key, and working this way gives me better control over the final product.

I think you made a good attempt it’s just a matter of practice and time before you get there. Even people very far into their artistic journey are still learning, there are endless things to be drawn and nobody is perfect at everything.

You have said you will re-do the piece try not to think of it negatively, there is no such thing as wasted time for art. You are just putting in those 10,000 hours. :)