Use a tool like 7-Zip or WinRAR to extract the contents.
If you are using the Cemu Emulator , you can install this DLC by selecting File > Install game title, update, or DLC and navigating to the meta.xml file within the extracted DLC folder. MK8-USA-DLCs-LOADIINE-ZIPERTO.rar
Typically includes the Mercedes-Benz x Mario Kart 8 update, as well as DLC Packs 1 and 2 (Legend of Zelda and Animal Crossing packs), adding new characters like Link and Isabelle, and 16 additional tracks. How to Use with Loadiine Use a tool like 7-Zip or WinRAR to extract the contents