Pycharm 2022.2.4 Community Packages - Error loading pacakge list: Connection reset 关注

First time using Pycharm and trying to add a package.   File->Settings->Python Interpreter "+" button on package list

I get the error in "Error loading pacakge list:  Connection reset" .   I'm sitting behind corporate firewall and we do have an internal repository that I'd be prepared to enter if I could get to the dialog box that allows me to enter that information.   But there is only an "OK" button on the error dialog and when I press that I get a blank list of pacakges and the "Install Package" button is greyed out.  Reloading the list give me the same error.

Is there a way to edit some configuration file manually to reset the "default" package path that is used?   Or perhaps there's some other configuration screen where this default reepository path can be modified.   In some other postings on the internet I see a "Manage Repositories" button - but that button is not on my screen.