Standard keywords for describing action keys cross operating system

So I’m involved in developing a web application which will allow user to maintain keyboard shortcuts for different actions. I’m facing two challenges :-

  1. How to listen to keypress of ctrl, shift, f1-f12, tab etc. ?

  2. User will input some keyword for keys. For example for the shortcut "ctrl+R", user will enter "ctrl+R". But my query is whether command in macOS and ctrl in windows have a standard keyword, so user can use same keyword despite being on different operating systems.
    I have searched through the net, but have no found no such web or OS standard.
    Any help or direction is greatly appreciated!!

Source: Windows Questions