This is the code for a 2D game engine that more or less runs dragon quest, sort of....not really...kind of. Here's a video: https://www.youtube.com/watch?v=JFxIZwer4JU
It's mostly written in C while using strings and vectors because I'm lazy, but almost never classes because those are garbage. If you find classes in this, either I didn't write it, or I made the terrible decision to write a class.
This tutorial I wrote may or may not help you run this code, idk, it's been a white: https://www.strivix.com/learn-programming/learn-sdl/learn-sdl2