Hello guys, my name is Giorgi and i'm newbie game developer i'm learning Pixel art and after pixel art  i want learn C# and don't know how and where start i'm bad with programming language and know only HTML/CSS

Pick up a good C# book like C# 7.0 in a Nutshell: The Definitive Reference. You can also check out Microsoft directly for resources:

https://docs.microsoft.com/en-us/dotnet/csharp/quick-starts/

https://docs.microsoft.com/en-us/dotnet/csharp/programming-guide/

Then you can pick up an Engine like Unity, very popular for new programmers and C# developers.

https://unity3d.com/

or you can look into MonoGame: http://www.monogame.net/

Besides all of this, you just need a lot of time and hands on practice. If you have more questions regarding code then post back.