Some books follow the same pattern, some don't. That's okay. Many of my favorite books aren't told "in order", and instead bounce around in time. It's one interesting way for an author to slowly reveal a story to their readers.
Stories that are told "in order" don't have to be written that way by the author, however. Putting it all together may not happen until much later. That's almost always true for me.
My first novel, An Unusual Path, as well as the novel I am working on now, are both stories told in chronological order as the events happened. However, there were written COMPLETELY out of order. With both of them, I wrote the beginning first, but the ending was written not long after that. Everything in the middle came together as bits and pieces that were later placed together once everything was finished.
The biggest reason for this is that I have a broad idea for the story from the beginning, know where I want it to go, and by writing the ending I know what I'm working towards. It gives me a goal to shoot for.
Another reason is that I get inspired by various parts of the story at different times. For example, in An Unusual Path, I knew that the characters of Clark and Amy were going to get into a fight, but at first I didn't know what they were going to fight over. I wrote the aftermath of the fight where Amy screams about his priorities and hangs up on Clark, and then walked away from it for a while. Later I came back and finished that part of the story when the inspiration finally came.
One of the most important details to keep in mind when writing out of order in the story is to keep your facts straight. If a couple mention where they met, as an author you need to make sure that they actual story of their meeting matches up. That means A LOT of editing as the story develops.
Keep notes on some of those details, because discrepancies in your story will only frustrate your audience. If you can't keep it straight, how can you expect your readers to?
When it comes to writing out of order, here's what works for me-
I like to think of moments or conversations within a story as scenes in a movie. I write each of those scenes separately, and then save them into individual documents.
Sometimes those later become chapters, sometimes not. While some scenes are fifteen pages long, others are a single sheet. Those details are unimportant. I repeat, UNIMPORTANT. It amazes me the things writers get hung up on.
When I feel like I have written all of the scenes in the story, I then piece them all together in the order they need to be in, and that is really my first true First Draft. I then read the entire thing from cover to cover, probably making a million notes along the way.
When you get to that point, take a moment and celebrate how much you've accomplished. You are on your way to a fantastic finished product.