Hi,
Sorry, the regular VC++ projects follow the Visual Studio’s separation between source and header files.
If you would like to avoid it, please try using the Advanced CMake Project Subsystem instead. It allows a fine-grain control over grouping and filtering of sources in Solution Explorer. Also CMake-based projects can be built outside Visual Studio/VisualGDB, so you won’t lose the ability to build your project on a different machine, or on a build server.