In the sample code, this is how you get the Home page from a .cshtml file
var homePage = CurrentPage.AncestorsOrSelf(1).First();
Now, how do I get a specific page/node (not related to current page, eg. the News page) by its ID?
You can use exactly the same approach but use .Where(x => x.Id == newsPageId)
.
Alternatively, you can use @Umbraco.TypedContent(newsPageId)
or @Umbraco.Content(newsPageId)
.