Some devices (Dell, HP, Lenovo, etc.) include a specific "HEVC Video Extensions from the Device Manufacturer." This is only free if your computer came with it pre-installed. You cannot download that version manually for free.
Microsoft sells the standard "HEVC Video Extensions" in the Microsoft Store. It is a paid license due to patent royalties. hevc video extensions download free
Install VLC Media Player from videolan.org to play your HEVC files for free and without any hassle. Some devices (Dell, HP, Lenovo, etc