I'm gonna just list some languages and rate them at the end.
-- JS, you must also know or learn HTML, CSS and other technologies that come with it (bootstrap, etc.).
-- Python, you pretty much need to know the same.
So basically these languages are only the "best" to learn if you you plan on learning a lot more with it.
-- C#, faster than JS and Python, and with .NET6 it is more than easy enough to start with and offers a wider range of ways to apply to language to real applications (web, desktop, mobile, etc.).
-- Java, also not a bad option, but it's not as easy to start with as C# and it doesn't offer the same ecosystem of resources and tools as C# (.NET)
-- C & C++, will get you into systems development and will generally teach you more lower-level concepts. I prefer C++ for it's versatility and general ecosystem.
-- Rust, for fast and safe applications, usually in systems development
-- Go, it's more for cloud and web solutions
Both are newer than the previous languages but their popularity is growing fast. I think Go offers more opportunities at the moment, but that doesn't mean Rust is bad.
So basically:
If you don't know which industry you want to get into but you still want to learn a good language: C# is the best to learn in my opinion.
If you want to get into web development: JS (with HTML/CSS obviously).
If you want to get into game development: C# and C++.
If you want to get into Data Science or AI/ML: Python.
If you want to get into systems/low level development: C and C++ (C++ if you only want to choose 1).
