I'm going down the road of publishing a photo book on a documentary project I've been working on for 25 years.
Vincent Johnson
The most valuable thing you can have is a rehearsal. I'd suggest a self-publish effort first, especially if you're new to graphic design and book authoring.
Blurb works well and is affordable. Wait for the 40% off sales, which occur regularly.
Others may chime in that the image quality is poor, but I submit that it's good enough for learning if not for collectors, museums or fine art sales. It's definitely good enough for me and I'm a retired Hollywood cinematographer with six-foot-wide, self-printed images on my walls.

I love browsing through the books, my images look great, and so far, everyone that's read them has been very complimentary.
I've done four coffee table books so far, each one streets ahead of its predecessor. It's a steep, but fun learning curve, easily one of the most satisfying challenges I've met in fifty years as a photographer.
Basically, the procedure begins with tech layout, materials choice (paper type, size, etc.) and then the creative component, where you place images, write text and create a story. Once you're satisfied, you render out a PDF which gets sent to Blurb. Your finished book arrives soon after - a delightful experience.
The best tool for the job is Adobe InDesign, available as a monthly subscription if you're not a Creative Cloud subscriber. Affinity Publisher might suffice, but it doesn't offer the convenience and guaranteed accuracy that the Blurb InDesign plug-in offers. Blurb offers their own tool called "Bookwright", I believe. It will probably suffice. It's free. I wouldn't attempt using Lightroom's "Book" module. Others may have chime in with more recent experience with this tool than me.
Getting the technicalities of the layout are important at the beginning. The creative part of the layout comes later and is tedious to repair if your original layout is flawed. Blurb is draconian with its specs.
My latest book is 120 pages, uses the highest spec materials, and is the largest size available. It cost about $250 for the first copy.
It's a highly recommended, very satisfying endeavour. It is a time sink.
Good luck!