Download the language pack files ( .cab files) for the extra language you want to add.
cd C:\LanguagePack
Here's the step-by-step guide to offline install a Microsoft Windows 10 language pack: Microsoft Windows 10 Language Pack Offline Install -Extra
First, download the language pack files ( .cab files) for the language you want to install. You can download these files from Microsoft's official website or other reliable sources. Make sure to download the correct files for your Windows 10 architecture (32-bit or 64-bit). Download the language pack files (
dism /online /add-package /packagepath:C:\LanguagePack\fr-FR.cab This command installs the French language pack. Microsoft Windows 10 Language Pack Offline Install -Extra
Create a new folder on your device to store the language pack files. For example, you can create a folder named LanguagePack in the C:\ drive.