Tell me if you need help (32-bit vs 64-bit). Ask for the official download link for the Croatian pack.
A "repack" is an installation package created by a third party rather than the original developer. In the context of Office 2016 language packs, a repack might offer: Size Efficiency
Change your display language to Croatian. Office 2016 will attempt to match the OS language if the pack is installed, but without the actual LP, you get mixed results.
: Official methods often rely on the "Click-to-Run" installer, which requires an active internet connection. Repacks are typically standalone files that allow for completely offline setup. Simplified Deployment