A newsgroup is part of the usenet news system. Usenet news is a collection of thousands of different discussion groups on a huge variety of topics. Participants write articles which can then be read by any person who has access to the usenet news system.
In order to have access to the usenet news system, your site must be set up for usenet news. You should ask your system administrator or support staff whether usenet news is available, and how to access it. All commercial on-line services that I know of offer usenet news access.
If usenet news is available at your site, and your world wide web browser is set up correctly, you should be able to access the soc.couples.wedding newsgroup by selecting the soc.couples.wedding link in this sentence.
Alternatively, there are web sites where you can read usenet news, such as: