They Keyboard.press() command accept modifiers per the documentation . You may need to do multiple press() commands before releasing.
For example, if you want to launch ExplorerFile Explorer you could use:
Keyboard.press(KEY_LEFT_GUI); Keyboard.press('e'); Keyboard.releaseAll(); This is equivalent to shortcut keys windows + eWin + E.
The modifier GUI is what stands in for the "command key" which is the Windows Logo on a PC or Clover clover (⌘) on a Mac.
I am not havingdon't have any restriction on the higher value on my board (Pro MicroPro Micro), as indicated by @frarugi87.