I pretty much agree with the entirety of this answer, and here's a list of game engines and the languages they're implemented and scripted with https://en.wikipedia.org/wiki/List_of_game_engines
I see a form of this question asked a lot in general software development, "What is the one programming language I should learn?" and I think it would be a mistake to plan on just learning one language. As you can see there are a lot of languages in use (sometimes in the same game engine) and it would expand your options if you're open to learning more than one, and while some languages are pretty similar, others have much different styles and approaches to programming, so kind of like learning multiple human languages, it'll expand your brain.