If you're working on a Mac with OS Catalina or later, there is a known issue with using Unity Hub 2.2.2 (and earlier versions) to install Unity with the preceding steps. If that's the case for you, take a deep breath and go to the Unity download archive and grab the version you need (https://unity3d.com/get-unity/download/archive). Remember to use the Downloads (Mac) option instead of the Unity Hub download:
If you're working on Windows and run into similar install issues, the steps we just took will also work just fine.
The download is a normal application installer since it's a .dmg file. Open it up, follow the instructions, and you'll be ready to go in no time!
All of the examples and screenshots for this book were created and captured using Unity 2020.1.0a20. If you're using a newer version, things might look slightly different in the Unity editor, but this shouldn't affect you following along.
Now that Unity Hub...
