For One Dreamer players. this guide is about Welcome to BACKEND, [How to unlock achievement] main.cpp #include <iostream> #include “onedream.h”using namespace std; public void Prologue() { cout << “Hello, Dreamers!” << ‘\n’; cout << “this guide will help you unlock Welcome to BACKEND achievement” << ‘\n’; cout << “SPOILER AHEAD, DONT READ THIS GUIDE UNTIL…