This blog post contains a mind map of language features starting from C# 1 up til now - including some of the new C# 12 features that will be released in November 2023.
The C# 12 features are, of course currently in testing, so the scope can shift (new features will be added and maybe even some will be dropped - time will tell).
Update 11th Februrary 2023: I created a newer version, where all language features contain a link with examples and description! The original version can be found down below!
Here is the preview of a clickable version. Open the SVG directly and you can click on the nodes, which will forward you to resources that explain the language feature.