Adding files to audio plugin project in Visual Studio 2017

Hi,
I’m not sure if I’m stupid or what but I have this issue. I created a project for vst audio plugin and exported it to visual studio 2017. Everything works fine except that I don’t know where should I add a new file to the project. If I add it to Source folder in Visual Studio it is added to Builds subdirectory and is not visible from files generated by Projucer. The same for SharedCode project. How am I suppose to add new source and header files to the project?

Ideally you add them in the Projucer and click “Save project and open in IDE”.
Select Source in the files tab and click the plus (+) icon in the lower right corner.
You can also move the created file afterwards, if you want your files in a specific order.

HTH