Adding custom variables to "GameUserSettings"

Hi Guys,

I have a fully functional options menu to set all the desired variables inside the GameUserSettings.ini.
However, I’d like to add variables like “Music Volume”, “Ingame Music Volume” and the likes, and save those to the same ini file.

I have zero C++ experience, so I don’t even know fully how to construct this question, I guess I am asking if it is doable to add C++ code (variables) in a file and make those accessible in blueprint.
Somewhere, there must be a file that holds the standard GameUserSettings variable in C++ where I can add this, and make them accessible in the same way.

Is there anybody who can point me in the right direction? I think if I know where to start I will get it done.
It will be my first C++ learning experience, I’d have to get a little bit decent at it at some point to finish my game.