How to export 1 Entries type ("news") from Craft to Wordpress
Most people are going the other way. Is there a particular reason you want to downgrade? ;-)

Being serious though...

If you need the entries in a CSV format then yes you could use an export plugin such as Sprout or Export. Or you could make a template that outputs your content in the format required. 

If you choose a plugin, then you'd need to read the documentation to find out how to set that up.

As for importing into Wordpress. That's dependent on your Wordpress setup and what you are using to do the import and is probably outside the scope of this particular Stack Exchange site.

But bear in mind that Craft is incredibly flexible so if the reason you're wanting to switch is related to particular functionality it could almost certainly be achieved with Craft.