Where is the builtin git tooling for showing side by side diff with proper syntax and different parts highlighting, and make it possible to turn my review comme

Where is the builtin git tooling for showing side by side diff with proper syntax and different parts highlighting, and make it possible to turn my review comments back to the "bottom-posting" style text emails interleaved with the inline diff everyone on the mailing list strongly insisting? I'm sorry but I'm a stupid noob and my eye is not able to parse codes without syntax highlighting.