Hi jinyicool, on the Mac your appdata folder is in your home directory, under Library/Application Support/Moi.

So the full path is /Users/[your user name]/Library/Application Support/Moi (or ~/Library/Application Support/Moi).

Note that since OSX Lion Apple decided to hide the Library folder by default from Finder. You can use the "Go to folder" menu option and enter it, or use Cmd+Shift+. to temporarily show hidden files, or use one of the methods mentioned here:
http://osxdaily.com/2016/12/12/show-user-library-folder-macos-sierra/

- MIchael