, and welcome.
I don't think there is any standard way of doing this.... after the fact. You might Google up info on /etc/skel
to see if that would be useful for all new users
to inherit certain settings, but it doesn't retroactively change existing users settings. I'm guessing you'll have to do something like this:
1) Identify config files that you've changed that you want to pass on to other users.
2) Copy those config files to each new user.
3) Possibly change ownership and permissions of the files that you copy.
That's all pretty klutzy though. Once you figure it all out, you could probably make it a bit easier with some scripting, but it sounds like it might be an ever-changing project.