PDI is a multiplatform tool. This means that no matter which operating system you have, you will be able to work with the tool. The only prerequisite is to have JVM 1.8 installed. You will also need an Office suite, for example, Open Office or Libre Office, and a good text editor, for example, Sublime III or Notepad ++. Access to a relational database is recommended. Suggested engines are MySQL and PostgreSQL, but could be others of your choice as well.
Having an internet connection while reading is extremely useful too. Several links are provided throughout the book that complements what is explained. Besides, there is the PDI forum where you may search or post doubts if you are stuck with something.