Most languages are not very different as far as the semantics go. The Algol family, for example (Pascal, C, C#, Java, Lua, Python, …) - if you know any of them

Most languages are not very different as far as the semantics go. The Algol family, for example (Pascal, C, C#, Java, Lua, Python, …) - if you know any of them well, it’s easy to pick the others up quickly. But a language includes idioms, the eco system, and even conventions like camelCase vs PascalCase vs snake_case. Until you master these, all code you write will be alien and awkward to the natives. C++ has become its own thing, where you have to study an awful lot just to be able to _read_ it, but it is otherwise of the same family. I’ve only been programming for 40 years, have professionally done so in over 10 languages, and nowadays preach to only pay attention to paradigms rather than languages. You don’t think differently when working in C# vs Java, and not materially different than e.g. C, if you are writing idiomatic code. But Lisp, APL, Prolog, Haskell - idiomatic code in any of these languages does not resemble one in any of the others (or the Algols) - they each offer a very different way to look at things. And your C code will be Better if you grok them, even if you don’t use them.