You will need to provide a little more information on the module. You've posted this in the Geoprocessing group. Is this a scripting module and question? Or a general how to localize ArcGIS? If strictly an ArcGIS installation question, you may want to move this to New to GIS since there may be more views of the question there. Also, you may want to change the description from "Hello" to something that will describe you question...that will also get more users to look at your question.
For additional info on Geonet, check out the various documents on GeoNet Help
By the way, I am not familiar with the module linguistic either....but it sounds like maybe it is a localization related topic.
Are you looking for a "Language pack"? Do you have the installation program (executable) already? If you don't, you should be able to download it from the Customer Care account. If it's not available there, you may have to contact your international distributor for access.
If you have installed a language pack, you must also update the ArcGIS Administrator to enable it.
Open ArcGIS Administrator. It should show the ArcGIS Configuration Information page. At the lower right, click the Advanced button.
On the Advanced Configuration dialog, change the Display Language. OK all dialogs.