You may want to look at F#. Because it's .NET you have a large list of libraries you can use
All that said, probably C#.
A lot of what you’ll learn when you first learn programming is going to be applicable in any language though. Once you’re comfortable with C#, and can understand the difference between imperative, object-oriented, and functional programming, you’ll be in a good place to check out F# (or any other language, really).
Good luck with your learning!