Is there any tutorial, how to use this module?
There's a "Code Examples" sticky in this forum, and there is also documentation in the wiki.
Most of the time, the module page will have a link to a setup tutorial.
[url=http://doc.silverstripe.org/doku.php?id=modules:image_gallery&s=image%20gallery]Here's a link to the wiki page UC is referring to.[/url]