Use mono [1]! Then write your first console application [2]. Or read [3] to learn about the language. And then maybe check out some trending github projects [4]!

[1] http://www.mono-project.com/

[2] https://msdn.microsoft.com/en-us/library/k1sx6ed2.aspx

[3] http://learnxinyminutes.com/docs/csharp/

[4] https://github.com/trending?l=csharp