Any USB or Bluetooth keyboard works. macOS maps the Windows key to ⌘ and Alt to ⌥, which puts ⌘ one key further from the space bar than on a Mac keyboard. Many people swap them so that the key next to the space bar is ⌘ again: System Settings → Keyboard → Keyboard Shortcuts → Modifier Keys, pick the keyboard, and exchange Option and Command.

The extra keys:

  • Home, End, PgUp, PgDn work, with the Mac meaning: Home and End scroll the document rather than moving the cursor to the line ends.
  • Delete deletes forward, as on Windows. Backspace is Backspace.
  • PrtSc, Scroll Lock and Pause do nothing by default; a keyboard tool can give them a job.
  • Insert does nothing. Overtype mode does not exist on the Mac.
  • The function keys act as F1 to F12 unless the keyboard has its own media layer.

Keyboards with a Mac layout printed on the keys exist, but a plain PC keyboard with the modifiers swapped is the same thing.