Creating New Language
Creating a new language means you will have to translate all of the text for PrestaShop’s front-end, back-end, modules, etc.To do that you have to download the required language pack file from the PrestaShop official website. Once you have downloaded the file,
Go to Localization -> Translations.
Now, simply browse to the language pack file and press the Import button. The language pack will be installed in few seconds.