To start learning C#, firstly you should have computer knowledge. With that, if you have a prior learning experience in C or C#, then it would be great.
To start with C#, first install Visual Studio. The current version is Visual Studio 2017.
If you want to avoid the hassles of installing a bulky Visual Studio IDE, then you can begin with Online Compilers. The top online compilers to run C# programs are −
Coding ground
DotNetFiddle
Both of the above are intelligent compilers. Just go there, type the C# code and run it. That’s it!