For many COD 2 does not have the common Steam.dll and Steam2.dll which is steams way of being able to talk with the game, so you will have to find them and add them to the COD 2 directory

These can be found in C:/Program Files (x86)/Steam

Copy both Steam.dll and Steam2.dll and past them inside of Call of Duty 2s directory in SteamLibrary/steamapps/Common/Call of Duty 2 (You can also right click the game in your library and click "browse local files" to reach there too!)

This step is due to many users not having these required DLL files upon install and it will throw an error saying "Can't find steam" and won't launch.

Now that steam can actually talk to the game and launch, some like me will hit play, we see the cod 2 logo, then black screen, and then will close without ANY error.

So what was the culprit?
For many the mod I list below was its own fix, but it was actually MSI Afterburner Overlay in this case.
MSI Afterburner by itself didn't cause the issue but the issue was the OVERLAY.

Before playing COD2 turn off your MSI Afterburner overlay and it should get straight into the intro videos and main menu. If you are unable to reach the main menu, there may be another present issue not stated in this guide.

Steam and NVIDIA overlay don't seem to cause issues, but you are free to turn those off to be safe and any other overlays.

Get into the game and make a profile! Name it what you want then close the game, weird why are we closing? To answer that you need to change the profile CFG file. The game will simply crash for most when you change the resolution inside the game itself.

Navigate to your COD2 directory again, for reminder its:
If its on your main hard drive go to C:/Program Files x86/Steam/SteamLibrary/steamapps/common/Call of Duty 2

If it is not in your C directory for steam, it should look similar if you look into the drive it is installed on: (Letter)/Steam/SteamLibrary/Steamapps/Common/Call of Duty 2

Open up the folder named "main" then open "players" and then open the folder with your profile name, you will see a file called config.cfg, open it with notepad and you will have access to your settings! (If the config is not present create the file yourself)

There are 3 command lines you want to look for are:
seta r_mode
seta r_displayRefresh
seta r_lodscale

Set seta r_mode to your resolution, I have a 1440P monitor so I use 2550x1440, then for displayrefresh set it to what your Hz (refresh rate) is, mine is 165 so I put "165 Hz"

Then set lodscale to 1 (it is the highest quality and will provide the furthest you can get in lod without modding)

(RECOMMENDED BUT NOT REQUIRED!)
This game does have SEVERE pop ins for assets, what I used to fix this was a mod which you can get here:
https://www.moddb.com/downloads/call-of-duty-2-single-player-improvement

This mod has a replacement .exe file and a replacement DLL file. Replacing them with this mod allows for the console to be on by default, a FOV default of 90 (changeable), and sets to max the lodbias and scale for the game. Highly recommended for a smoother experience.

Hopefully after all that, if you want to you can change all other options in the main menu and start the campaign!

I can't guarantee it will work for everyone but it may help somebody, and that is the point of this guide.

There are also other guides on steams for issues that are not presented here in this guide, please refer to those for issues not in this guide for as they also put time into their guides as well! However I will do my best to respond here in the comments if there is any further questions.

Happy hunting comrades.