Google chrome can't access my files and folders

I'm not sure where you can manually configure these preferences once you've disallowed Chrome access. The section of System Preferences you mention would seem like the logical and appropriate location.

However, if you want Chrome to prompt you to allow it to access your folders, then try deleting the Chrome preferences within the hidden Library folder within your home user folder. Option-click the "Go" menu to reveal the hidden "Library" option which will open a Finder window. Then navigate to the Chrome preferences and delete the Chrome .plist preference file. I'm not sure exactly where the Chrome preferences are stored or which preference file it may be. Look in the "Preferences" folder and look within the "Application Support" folder within the hidden Library folder. Make sure to quit Chrome before deleting any preference files. There is a chance you may need to temporarily delete the whole Chrome folder from Application Support. Once you get macOS configured you can most likely restore your preference files/folder.

There is a chance this won't make a difference if macOS already considers this access is already set/configured. I don't know how this works or is triggered. Maybe if Chrome has to create the whole Chrome folder within "~/Library/Application Support" Chrome knows it is running for the first time and triggers the macOS notification to allow access to certain folders.