You do not "install" a video file; you open it using a media player that supports the MKV or MP4 container:
If you are looking for a "report" regarding its installation or safety, please consider the following security risks associated with this specific type of file: Potential Security Risks hornyhema20251080pwebdlhindiaac20x264 install
If you prefer a manual approach, copy the libh264_ac20.so file to /usr/lib/x86_64-linux-gnu/ and run sudo ldconfig yourself. You do not "install" a video file; you