C# and VB share the same .NET libraries. The only difference is the C# syntax which is easily looked up in the C# programming guide. I moved to C# years ago and as I recall I became very comfortable with the C# syntax within a week of programming. It's not a giant learning curve if you understand programming basics. The type declaration, brackets, ending every line with a semicolon, and array [] are the toughest habits to establish when moving from VB.
so I wish to switch most of my web projects like https://cesaricacroatia.com/ or https://kritikaz.com in fact over 50 of them to c#.
I don't recommend converting working VB applications to C#. The only reason to update the language is if you plan to migrate the applications to ASP.NET Core; .NET 6.
I think the best approach is simply starting with latest framework. Go through a few ASP.NET Core tutorials and learn C# along the way. Any new development should be in ASP.NET Core anyway.
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