Your first question would be answered as, "Yes! We can build websites using JavaScript and its libraries". But you're wrong while picking the right language.
Since you've already learnt C# and you just want to use a language which you can use to build websites, why are you afraid of using ASP.NET? ASP.NET used C# language as the server-side and simple HTML for rendering the results on the screen. It won't take much time for you to work with ASP.NET, since you already know the syntax of C# and how you can use it to interact.
Here is a tip by me, to you:
Why Use ASP.NET for Web Development[
^]
Secondly, I would like to ask you, don't move to PHP, PHP and C# are totally different, you will have to learn it since the beginning. JavaScript and node.js are not much different, but still since you're good at C#, start your process with ASP.NET. Almost all of the giants are moving toward ASP.NET, some are using PHP right now, and JavaScript basically is a client-side language, so who knows tomorrow it will be a preferred server-side language or will be cut short to a client-side language only?
So, at the end my bid will be
ASP.NET!
http://asp.net[
^]