If you're looking to follow the OOTB configuration for blog posts then it won't be as easy as Chetan suggest to import the news items into blog posts. Kentico out of the box blog posts have this structure:
Blog Month (Month - Year)
- Blog post (Name of blog post)
So when you import your news items you have to specify a path to import them on. If you have a few it's not bad to just copy and paste, but if you have hundreds of them it will take you a while. You'll need to either manually go in and create the blog month object or run an import on the months first, then run a separate import for all posts under each month/year combination.
First import, imports all the months.
Second import imports all the posts under /blog/april-2016
Third import imports all the posts under /blog/march-2016
So as I mentioned it's not a simple import if you have a lot of posts and follow the structure in place by Kentico.