This wizard will configure a news gateway: your server will be able to fetch newsgroups from an external news server (usually the one of your service provider) and make them visible to your internal network. Therefore the first step is to specify which external news server you want to use.
Then you need to specify the interval (in hours) between each refresh. Do not specify too high an interval: news evolves rapidly, as does pretty much everything else on the Internet for that matter...