Hi,
If you have previously developed your web site in Kentico CMS, you can use export/import feature of Kentico CMS to manage the movement of web sites. For more information about import/export feature, please refer to following documentation:
http://devnet.kentico.com/docs/devguide/export_and_import_overview.htmIf you want to install one of the pre-defined web sites from web templates, you need to navigate into CMS Site Manager -> Sites -> New site wizard -> Use web site template and choose your desired one.
Best Regards,
Miroslav Remias