Trying to find a way to open & edit the library files that generates names for NPCs in a game.

I suspect it’s in one of the DLL files that make up most of the game (rest is unity), but I am a semi-Luddite with marginal IT-skills. Tried Visual Studio, but simply trying to open any of the game’s DLL files with it didn’t work, I’d need to know the language the game is written in and get me the right extension for VS to be able to read it, I guess.

So how do I find out the language, and what would be the best program & easiest route for a noob like me to find & access the files I want/need to edit? Is VS noob-friendly or is there an easier alternative to achieve what I want?
And most importantly, where can I find a tutorial – preferably one that some IT-illiterate old-timer whose first language is not english can grasp – so I don’t keep bugging the pros in here about it^^.