The issues that arise when getting a Linux distribution working on a Mac usually revolve around two problem areas: getting an installer to work correctly with the Mac, and finding and installing all the needed drivers so the essential parts of the Mac work.
This project is for advanced users who have the time to work through issues that may develop along the way and are willing to reinstall macOS and their data if problems occur during the process. Many Linux distributions can run nicely on a Mac, though there can be challenges to installing and configuring the OS. You can still install on an external drive, however. You'll find the same processor families, graphics engines, networking chips, and a great deal more.
Under the hood, Mac's hardware is remarkably similar to most of the parts used in modern PCs.
