Under Configure tab > Language, you can choose the language of the interface labels and translate the course content into multiple languages using XLIFF export and import.
Here you can choose the language of the interface or add your custom translation.
In the All-in-One template, currently Afrikaans, Arabic, Bulgarian, Croatian, Czech, Chinese (Simplified), Chinese (Traditional), Danish, Dutch, English, Finnish, French, German, Hungarian, Italian, Japanese, Latvian, Norwegian (Bokmål), Norwegian (Nynorsk), Polish, Portuguese, Russian, Slovakian, Slovenian, Spanish, Swedish and Ukrainian are available. More languages will be added soon.
All text items of the template interface (button texts, titles and headings, field names, error messages, validation messages, etc.) can be also translated into any other language.
To add your custom translation, in the language dropdown select Custom. In the Translation column, you can replace the default English texts with your own translations.
NOTE: The interface language depends on your browser language.