Editors are essential in the publishing industry! I cannot stress this enough. A great book will remain a poor one if it is riddled with spelling and grammatical errors, so do not think you can “wing it” by editing your book yourself.
The link below has hundreds of editors who offer a wide range of services.
Please do your own research! I make no warranties or claims about the quality or creditability of these listed editors, so it is in your own best interest to look at the work they’ve done on similar books and request a few samples of their editorial services.
You can view them here:
https://www.goodreads.com/topic/show/837692-editors
Best,
Vincent Lowry