I started reading this book about 2 years too late, in my last year of my computer science degree. I have only now finished it, and I had to skim some of the last chapters. It's a pretty monumental task to read it through, and I cannot help but wonder how much it have taken to write it. Bishop has extraordinary insight into the Bayesian treatment in pattern recognition, and this is expressed here in, sometimes excruciating, details. If you're a beginner, I would just read the first 4 or so chapters, maybe chapter 8 and skim some of the variational inference sections. For more advanced learners, the later chapters provide some excellent detail on how to go beyond the basics.
I'm a little sad that this book was not a part of my official coursework, as I have only later discovered how relevant much of the content was for a significant part of my courses, and even worse, my thesis (where variational autoencoders and, hidden markov models and Bayesian ensemble models were at the center, all of which are either described directly in this book, or given foundation). The variational autoencoder would fit right in (which rose to prominence after the book was written).
Chapter 5 on neural networks is good, but it feels disconnected from the rest of the book. Still, it's a good chapter in itself, and even though a lot is happening and has happened since the chapter was written, the foundations described here remain the same. People might use ReLU as activation now, and there are a few new tricks, but the foundations remain the same, such as perceptrons, backpropagation and activation functions.
Bishop is not the most pedagogical author, especially if you read more than the first few chapters, so if you need someone to hold your hand while reading, this is probably not the best place to start. In any case, the book seems great as a reference and if you like this kind of stuff, you should definitely read it at some point.