C++ - Need help with c++ basic game code structure

I'd like to start off by saying, I do a lot of research before attempting forums and I know to use the "search" feature before posting. I've yet to find a helpful post and even reviewing several source codes has not brought me to a solid enough answer to continue on my own with confidence in my coding.

I'm looking to put together a "shell" game from which to hone my game programming abilities. I want to make this shell in such a manner that the potiential functionality of a full, though simple, game can be constructed upon it in an organized manner. I'm relatively new to game coding, but have a solid understanding of c++; i'm not pro, but i've made a couple moderatly useful programs.

I've worked through some of the basics of game programming, but my code is sloppy and, at times, a task in itself to find where things are. I'm not expecting to put out a masterpiece and know to start with very small, simple games. I've been through some game tutorials and have made some basic games, but the code structure is never there. Frustrated with researching, here's what i'm looking to do (the short version) with my main.cpp

1. Is the below even remotly close to any "standard" or even a practical setup for potentially large games?
2. I want WINAPI WinMain to create my window in the graphics manager function, so how do I make windows "enter" my program without main being on the outside?

Any help is greatly appreciated, apologies if post is total noob.


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set global variables

Graphics manager{};
Audio manager{};
Joystick manager{};
game logic{};

msg loop{};
clean up{};