LNK 2001 and LNK 1120 C++ error

See more:

C++

C++/CLI

compilation

I just want to make a Windows Form in C++. After opening a template, the codeblock appears along with the designer.
Then, I just want to see if the compiler works, so I tried to compile and... it gives me these.

Build started...
1>------ Build started: Project: guessinggame, Configuration: Debug Win32 ------
1>mainWindow.cpp
1>mainWindow.obj : MSIL module encountered; incremental linking is disabled for MSIL; performing full link
1>LINK : error LNK2001: unresolved external symbol _main
1>C:\Users\Karl Steven Renevera\source\repos\guessinggame\Debug\guessinggame.exe : fatal error LNK1120: 1 unresolved externals
1>Done building project "guessinggame.vcxproj" -- FAILED.
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

I haven't changed ANYTHING YET.
Project Settings are already set to LINKER>System>SubSystem>Windows(/SUBSYSTEM:WINDOWS)
and Entry Point>main

Here's the default code:

#pragma once

namespace guessinggame {

	using namespace System;
	using namespace System::ComponentModel;
	using namespace System::Collections;
	using namespace System::Windows::Forms;
	using namespace System::Data;
	using namespace System::Drawing;

	/// <summary>
	/// Summary for mainWindow
	/// </summary>
	public ref class mainWindow : public System::Windows::Forms::Form
	{
	public:
		mainWindow(void)
		{
			InitializeComponent();
			//
			//TODO: Add the constructor code here
			//
		}

	protected:
		/// <summary>
		/// Clean up any resources being used.
		/// </summary>
		~mainWindow()
		{
			if (components)
			{
				delete components;
			}
		}

	protected:

	protected:

	private:
		/// <summary>
		/// Required designer variable.
		/// </summary>
		System::ComponentModel::Container ^components;

#pragma region Windows Form Designer generated code
		/// <summary>
		/// Required method for Designer support - do not modify
		/// the contents of this method with the code editor.
		/// </summary>
		void InitializeComponent(void)
		{
			this->SuspendLayout();
			// 
			// mainWindow
			// 
			this->AutoScaleDimensions = System::Drawing::SizeF(8, 16);
			this->AutoScaleMode = 
                 System::Windows::Forms::AutoScaleMode::Font;
			this->ClientSize = System::Drawing::Size(1178, 474);
			this->Name = L"mainWindow";
			this->Text = L"mainWindow";
			this->ResumeLayout(false);

		}
#pragma endregion
	};
}

Please help me asap...

What I have tried:

I've already tried the FF:
re-installing VS2019
remaking the project by copy-pasting the code
tried WinForm C++ template
tried C++/clr empty template