In the top menu bar, click > Download Windows Support Software .
Installing Windows on an external drive is a "hack" for the power user. It is not the seamless experience Apple provides with a standard Boot Camp partition. However, for owners of Intel Macs with tiny 128GB or 256GB internal drives, it is a lifesaver. It grants the ability to run necessary Windows-only software without sacrificing the speed or storage of the primary macOS installation. install bootcamp on external drive