In QtCreator, in project view select "sources" item of project, right click,
select "Add new...", select "C++ Class" and click "Choose...", fill out both
pages of the C++ Class wizard (possibly renaming the putative non-unix C++
class source file from a ".c++" suffix to ".cpp") then click on "Finish" to
find a pair of files inserted in the project file and open for further
editing with the contents of those respective template headers inserted at
the top of the relevant file.

To configure this go to QtCreator "Options" -> "C++" -> "File Naming" and
browse for the template directory with the browser button on the bottom
line "Licence Template:"