Just when I published this post, I finally found what I asked for: This Guide on Saving and Loading Data on the GDScript Dude’s website was very easy to understand, unlike the other guides I found on the topic of ConfigFiles, which I could not understand. And once I also took a brief glance at the code in his Guide on Dictionaries, I also knew how to change the Save File values on the SaveData Singleton from the other scripts. I successfully used this to store the player’s Local Highscore in user://game_data.json.
Now i am using the same technique to store the Settings from the Pause Screen in a game_settings.json file. I know that I should be using ConfigFile instead to store the settings in user://config.cfg, but I already found something that works just as well, so why Should i learn this more complicated way to do the same thing?