all turing complete languages are equal. which basically means all programming languages are proven to be functionally identical, they just write things slightly differently. programming is really about understanding a handful of basic structures and concepts, and after that learning new languages is basically just finding out how each language writes these same exact things. it's not like learning natural languages at all. under the hood they all do the same, which is translate your code to the language your specific cpu and gpu uses.
so all roads lead to rome and it doesn't fundamentally matter which one you pick first. you'll be learning the same things on all of them. there are no huge mistakes you can do here, nothing you learn on one language will go to waste. in universities you'd often be taught the basics of programming in a completely extinct language like 'scheme', but it doesn't really matter because they're all the same.
so pick one that you CURRENTLY have use for. (and always pick one you actually have a project for, never waste your time 'just in case I one day need this language').
if you want to make a game in renpy python is the only language you'll have use for. it's horrible and not at all the 'easy to learn' language people keep parrotting it to be, but it doesn't really matter if the thing you'll use it requires python. and renpy 100% does. (well it doesn't REQUIRE it, but it's the only language you'll have use for with renpy.)
if you wanna use unity you learn c# which is far easier. if you wanna use unreal you learn c++. they're very close to the same thing, and when you'll be learning your next 20 languages most will make tons of sense coming from c/c++/c#.
basically it comes down to this: if you want to make your life easier with renpy, you choose python. but if you want to do ANY type of game (including VNs), you choose either unity or unreal engine.