To be clear, this is a kit that allows you to install PC components (which are not included) to build a PC that runs Windows. There is no official way to upgrade the Mac Pro with Apple components. If you really want to run macOS, you should be able to turn it into a Hackintosh after compiling it.
Bond has a goal of $10,000 for his Kickstarter, and a bid of $699 in Canadian currency (about $500 in the US) gets him a complete conversion kit. If you don’t have a Mac Pro but just want to contribute to the spirit of the project, you can contribute 10 Canadian dollars and your name will be mentioned in the final project video.
Apple discontinued the Mac Pro earlier this year, ending a 20-year run for the Mac Pro brand. It was last updated in 2023, when Apple launched it with an M2 Ultra chip. When this design was presented in 2019, it had Intel processors. Apple offers Mac Studio as its best Mac workstation, but it doesn’t have nearly the character of its old metal towers.