ln is a standard command in UNIX operating systems, like Linux or macOS. However it looks like you try to install in Windows. I am not author, so I am not sure if this is supported or not.
If it is not then I suggest you try to run under Windows Subsystem for Linux.
Hey @MWaser! Unfortunately we don’t support windows as a platform at that moment. Please try 'Windows Subsystem for Linux` or Linux/MacOs. I am sorry for the inconvenience!