I also read a lot, but not to copy from other authors, but to be inspired by their stories and also to reflect on which elements of the writing style I like well and which I like less. I think the knowledge and skills could also be well honed in a workshop. To see what my chances are, I contacted Novum Publishing with a sample of my book. I got feedback from the service publisher that they could see potential and that I should keep at it. I can contact them again when I am finished with my work and then they will see how they can support me on the way to publishing my book. However, I'm sure it will be some time before that happens. I've made good progress, but there's no end in sight yet. And when I'm done, I want to give the book to a few beta readers first and get feedback, and then start editing it myself. I think that will be a good piece of work again. But I'm looking forward to when the story is ready to be polished before handing the project over to professionals.
Learning from other authors does not mean copying them. Copying would be just changing the names in a story and then selling it as your story. But learning from other authors how to give a person a real character is not copying. You don't have to copy it 1:1, but you should learn from it.
You should always have the will to improve and develop. There are certainly several methods how you can do that. You should not assume that you know and can do everything. Even if you have already published several books, you have to adapt again and again. Readers often want something different and trends change.
Finish your book and then get back to that publisher. The publisher will know how to get feedback or will give you feedback themselves. You will certainly have to rewrite one or the other part of the book.