Depends on your definition of “know”. Honestly nowadays I don’t feel too scared to try something in any language.
I’m most proficient in Java and Python. In my free time I nowadays spend most of my time messing around with Haskell, Julia, or Rust. And I have some basic knowledge in a lot of other languages, including C, C++, C#, Kotlin, Groovy, Prolog, JavaScript, SQL, etc, etc.
But as I said in the beginning, I’m not too scared of learning something new. If someone were to ask me for a job where I’d be using Go or Kotlin or something then I’d be fairly confident that I could adjust quite quickly.