How to solve a circular dependency?

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C++

My problem is that I have a global_variables.h file which needs to know about the files :
- Debugger.h
- Window.h
- Input.h

My problem is that Input.h needs to know about Window.h, and needs to use several of it's functions and therefore it also needs the global_variables.h file, and now I have ran into a circular dependency.

The reason I'm using a Global_Variables.h file is because I knew many files would need to access my different game engine components, so I threw them into the Global_Variables.h file, which seemed like a good idea at first.¨

But, since I'm a beginner i didn't think of this problem that I'm now facing. :/

Here's some code examples :

Global_Variables.h :

#pragma once

#include "Debugger.h"
#include "Window.h"
#include "Input.h"

// The name of the game the engine is currently running.
static const std::string GAME_NAME = "SwEngine Testing";

// The debugging/logging and also error handling component of the engine.
static Debugger global_debugger;

// The window/rendering/graphics component of the engine.
static Window global_window;

// The input component of the engine.
// Handles events such as window closing, keyboard pressing and mouse moving.
static Input global_input;

And the input class is newly created, only has a destructor and a constructor as well as some comments.

So, how should I go about solving this problem? :)

What I have tried:

Have tried googling but haven't really found any good answers on how to solve the problem.
So, I have not really tried anything yet.