The downloads from Creality only include instructions and software for flashing the firmware from Windows. If you don't have access to a Windows machine there is another way: avrdude. However, there are a few steps you need to take to work out how to flash your printer.
These instructions refer specifically to the Ender 5 Plus but I've tried to make them a bit more open-ended so that you'll be able to work out how to do this for other printers in their range. They are fairly generic and therefore should work for both OSX/macOS and Linux users.