The coaching industry is huge these days, and without any regulations and often dubious certifications, my advice is to be careful when it comes to hiring a coach.
If you are a bookkeeper, you should only hire and work with a coach who has experience in our industry (and a LOT of experience).
Coaches can help you in a variety of ways, but the way I help as a bookkeeping mentor and coach is I share the systems, step-by-step processes, templates, emails, and documents I built from scratch.
You have bookkeeping skills, but what I teach is the mechanics of running a business. Those ever-elusive, hard-to-master, and ever-harder-to-implement operation components.
Oh - and I also really focus on cultivating leadership and a powerful mindset with my clients too. These are also crucial for building a high-functioning, super-profitable business.