I tried to make a list once and got hung up on the 'BookShots'. Those are the short, cheap thrillers he did for a while. Do they count as full books? They have ISBNs. What about the 'Murder, Interrupted' true crime stuff? I decided yes, because they're sold as books. But it shows how you have to set your own parameters before you start.
Have you tried looking on Pinterest? Sounds silly, but people create infographics for everything, including author book orders. Search 'James Patterson book list printable' there. You might find an aesthetically pleasing graphic that's designed to be pinned and printed. The quality varies, and it might not be exhaustive, but for a visual learner, a well-designed infographic can be more useful than a plain text list.
The man is a machine. I read an interview where he described his process, with detailed outlines and co-writers. Understanding that made the publication schedule make more sense. He's less a traditional novelist and more a showrunner for a TV series of books. The 'order' is just the airdate schedule for different shows in his network.
It's fascinating how his name became a brand. The 'complete book list' isn't really by James Patterson alone anymore; it's by 'James Patterson &'. The reading order for his ideas or outlines that others fleshed out. That changes how I view it. I follow the authors I like who co-write with him. If I enjoy Maxine Paetro's writing in Women's Murder Club, I might seek out her other work.
So, maybe order your reading by co-author? Read all the Patterson/Paetro books in order, then all the Patterson/Ledwidge books, and so on. That gives you a more consistent voice across the books you're reading, even if the protagonists change. It's a weirdly meta way to approach his bibliography, but it highlights how modern commercial fiction is produced.
I'm going to go against the grain and say start with the middle. Seriously. Pick up 'Pop Goes the Weasel' (Alex Cross #9) or 'The 6th Target' (Women's Murder Club #6). If you can enjoy a Patterson book plopped into an ongoing storyline and still get hooked, you'll know his formula works for you. Then you can go back and explore the earlier books to fill in the blanks. It's a fun experiment that removes the pressure of 'starting a journey.' These books are designed to be accessible, so you rarely feel completely adrift.
I appreciate the completists out there. There's a satisfaction in mapping it all out. For them, I'd suggest using a site like Goodreads. You can filter an author's books by publication date and then manually sort them into series. It's a project, but it'll give you the master list you crave. For casual readers, this is all way overkill.