It's a book for someone that already has some skills in deep learning. isn't a book for beginners.
Anoter funny fact is that this book contains some code errors, but are not too dangerous, and if you're agile with coding, you'll notice fast. Despite of that, it helped me a lot moving from tensorflow to PyTorch. I'll recommend it if you want to do the same, isn't a book for learning deep learning, for that task i'd recommend "Learning Deep Learning - Magnus Ekman", "Machine Learning - Aurelien Geron", or Francois Choillet books. Regardless of that, this book makes you to build an AlexNet, it covers some history and gives you good tips for a general Deep Learning Development. Im applying an using this concepts right now with some of personal projects. Another fact, this book was released in 2019, so pytorch wasn't well developed yet, remember that pytorch released date was 2017, so, nowadays pytorch doesn't contains any of the limitations that the book have mentioned, take that in mind (aka, you could do with the same coding more)