Hi Aradon,
Yes, it is possible to install the driver using the .INF files when you know how to go about it and if the device doesn't require other supporting files. (Doing this manually for devices like Ethernet Controllers is fine, but I would suggest installing the whole driver package for devices like Graphic Cards and Audio Chipsets)
However, most manufacturers these days offer a ready-to-install EXE file, to either install or update device drivers, and for good reason.
Referring to your question, I only specified Speccy as an option to determine your hardware details with all drivers installed, like with Driver Reviver (only more detailed). "Unknown Device Identifier" on the other hand, is the tool you should be using, when you are missing drivers on your computer. This utility helps detect the hardware based on its device ID and vendor ID. This can also be done manually by referring to the properties of the device and looking it up on sites likes PCI Database.
Please let me know if you have any questions.
Best regards,
ReviverSoft