so I tried to play on internet but I can't find the gamebox id, I looked on my game list there but there isn't any option to find it
If you go to "GOG.com" (in browser, NOT through Galaxy Client) and log in.
Go to your Library (top center of the screen)
search your games for "Heroes of Annihilated Empires"
Click "Heroes of Annihilated Empires" for the dropdown menu
Click "More" under the title next to System and language.
Click "Serial Keys" and it'll display the games keys for you.
Alternately if you're in need of automated assistance, download and install "GameRanger" and run it as admin.