If you see The specified service does not exist as an installed service , your INF file likely omitted the AddService directive. Windows needs to know that this driver runs as a system service.
Starting with Windows 10 (and enforced heavily in Windows 11), Microsoft requires all kernel-mode drivers to be digitally signed by a trusted authority. If you download an old or custom INF driver, Windows will refuse to load it. You can disable signature enforcement temporarily (for testing), but for daily use, you need a properly signed driver. inf drivers