Typically, sites like Hienzo provide compressed files (like .rar or .iso). You would usually need to extract these, run the setup file, and sometimes apply a "crack" or patch included in the folder to bypass DRM.
If you want the safest and most stable version of the game with full access to patches and online features, you can find it on: Steam Epic Games Store GOG.com biomutant-free-download-hienzo-com
If you are looking for information on downloading from Hienzo, What is Biomutant? Typically, sites like Hienzo provide compressed files (like
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