The file name typically looks like: AcroRdrDCx64_LangPack_LanguageCode.exe (e.g., ..._fr-FR.exe for French).
If the language you want is missing from the Preferences dropdown, you may need to install a language pack manually. This is common in enterprise environments where IT administrators install "English-only" versions to save space. adobe acrobat reader dc language pack
Adobe provides specific installers for and 64-bit versions of the application. 1. Official Download Sources adobe acrobat reader dc language pack