Dunno where to get Hades source code.

[HumbleLearningMonk]

Hello! I have a bought copy of Hades and I´m starting to learn programming. I had an idea for a small videogame which has a very similar mechanic to one in the game, and I wanted to check the code to see how it was resolved by the developers so I can learn. Is there any place where I could get the code to do this learning? 

Also, I´m very very new at this, so I don´t know if there is any easy way to start looking at game codes to learn from it (I was adviced to start looking into source code when I finished my basic training, which I´m promptly finishing.) like, if there is a website or platform to do it.

Thank you so much!