You'd have to contact your ISP and ask them or look on their on-line help pages if they have any. UseNet has pretty much gone by the wayside since the WWW became popular and many ISPs don't offer NNTP services. If your's doesn't then you'll have to either find a free news server out there or sign up at a pay site for $4-$5/month.
Even if your ISP has a UseNet News Server they may not carry the NewsGroups you are interested in. Some will start carrying them if you ask but it's up to each ISP...
For a list of possible free Usenet servers check:
http://freenews.maxbaud.net/
(This is a list of free servers but they are generally unreliable...)
A good pay service I use is:
http://www.usenetserver.com/
You can also read many groups by going to
Http://www.google.com and clicking on the "Groups" tab above the query box.