Hi simoneramo,
There are a few ways to approach this. If you want to use next/previous, we have a method for that:
{exp:channel:next_entry}
Next entry: <a href="http://{path=site/comments}">{title}</a>
{/exp:channel:next_entry}
{exp:channel:prev_entry}
Previous entry: <a href="http://{path=site/comments}">{title}</a>
{/exp:channel:prev_entry}
I you want numbered paging, we have that covered too:
{exp:channel:entries channel="news" orderby="date" sort="desc" limit="1" paginate="bottom"}
<h2>{title}</h2>
<p> {summary}<br />
{body}</p>
<p> {paginate}<br />
Page {current_page} of {total_pages} pages {pagination_links}<br />
{/paginate}<br />
{/exp:channel:entries}
You can even show one entry on the page and have a block for a list of other entries in the same or even different channels.
Cheers!