
MyCompLab is a dynamic, interactive online resource that gives you everything you need to become a better writer and researcher--all in one easy-to-use Web site. -- Back cover.
Thinking in Style, Pinker
Revising Prose, Lanham
Good Prose, Kidder
Once you understand style, either try for style they mostly talk about in that book (classical style), or if you want practical style then Revising Prose or Style: Toward Clarity and Grace are good.
> "I'm absolutely struggling with how to change the way I write to be less complex, when I myself don't recognize it as being verbose or overly complex in structure."
could be written more shortly and simply as:
> "I don't believe my writing is verbose or complex, so I don't know how to make it simpler."
Not picking on you, if I were writing that I'd probably end up with something closer to your first version in the first draft. Which is why you want to revise into a second draft.
Luckily there's a book that can help: "Revising Prose" by Lanham (http://amzn.to/2f9pUjN). Your local library probably has a copy. It's pretty entertaining read, too.
If you want a more extensive guide, "Style: Lessons in Clarity and Grace" (http://amzn.to/2f9zqDp) goes a lot further. Again, I read a copy from the library. Beyond the style of your prose, if you want a conceptual guide to business writing, see this review: https://codewithoutrules.com/2016/06/15/writing-book/
But "Revising Prose" will probably suffice.
Practice makes perfect, that's really all there is to it. A good book on writing style can help, but only if you use it. The Sense of Style by Steven Pinker and Revising Prose by Richard Lanham are my two favorites.
There are two other books I'd throw up with it—Revising Prose by Richard Lanham and The Elements of Style by Strunk and White.
Those three books together are a fantastic course in writing.