One of the C++ project that have influence my programming the most recently, which is to move to a style that is something between C and C++, is Dear ImGUI: https://github.com/ocornut/imgui
I had a quick look at the code but I would be interested in what "a style that is something between C and C++" actually entails.
Avoiding templates but using classes/namespaces? Minimizing use of the stl?
Also while ImGUI is great and the guy follows good coding practices - it's not at all what I would recommend for learning C++. Not only is it technically not C++, but the problem it solves (GUI-Framework and immediate on top) leads to some pretty hard to follow code with a lot of hidden global state.
I'm going to have nightmares tonight.