Hi!
On 'main page' and 'news' I have all news and all categories, but I want to create a few pages in 'navigator' where news will be segregate by category. One page - one category news. Is it possible?

I trying to type index.php?page=news&topic=16 but it does't work..

Obviously it won't work because there is no possibility to do that. You can use blog, it has content separated by categories

or you can use articles as news also, just edit the layout code in the pages/articles/index.php

and then make articles in the main block on the admin page