That's a tough one, out of the box the CommentsView control used to display the list of comments on the frontend does not contain paging functionality, and including it in the default control is not that trivial.
Generally the best solution would be to develop a YouTube-like comments functionality where you'll show just the first couple of comments, and then upon users request make AJAX calls to retrieve the next set of comments.
All the best,
the Telerik team
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