Where Are icons resources stored/hidden in macOS?

I want change or modify some icons and I can’t find location where these icons are hidden. I tried in odrive-package/resources but there is only main odrive.icns. Can someone tell me where icon of for eg. odrive folder is hidden in?

The main application and its resources are kept in $HOME/.odrive/bin/ver#here/odriveapp.app. Keep in mind that this location is changed whenever there is an update.