Is it possible to edit a Blueprint Project in C++?

So my question is, if it’s possible to open existing blueprints in c++. I need this for the Steamworks SDK. I wanna implement this in my Blueprint First Person project, but the SteamWorks SDK needs c++ code to run successfully. Please help!

You should probably look into the Online Subsystem features. It support steam as a platform. You can also add code to the project and re-parent the blueprint actors if you need lower level access than blueprints provide.