First you have to learn C. :roll: :razz:

You must translate the interface, type and constant definitions to a C and assemble them in a C header. This will be the import header for your library, and it should contain all datatypes, constants, interfaces etc etc, that are needed to work with your library.

Then the user can e.g Call The "MyEngine_Init" routine that is defined in that header to initialize the library and start working with it

First step is to learn how to create DLL's with exported functions, after that, learn how to use interfaces for Application <-> DLL communication. And finally, learn some C++ so you can make a C header for your lib.

Good luck