New documentation available at https://docs.openkm.com/kcenter/
The documentation at the https://www.openkm.com/wiki is definitivily deprecated.
Consider only use it, if you are user of OpenKM version 6.2 and older.
Click in the banner to close the warning.
OpenKM is a multi-language system which allows you to change the language of the user interface at any time during the session. In the "Tools / Languages" menu, you can select any of the languages installed by the administrator.