Regarding Facebook, you need to add the “App ID” code that you can obtain creating a new application on Facebook developers. Login with your account and click on the Add new app entry.
If the creation of the application was successful you will be redirected to a page like the one shown in the following image.
Then click on “Add Platform”, select “Website” and insert your site URL.
Now go to the “App Review” section and ensure the application is public.
The last step is to copy the APP ID and paste it into the plugin settings dashboard.