You need a signed driver to access the registers within the CPU. See if you can find a copy of the old WinRing0 driver. I think it has been out of development for over 15 years so it might be hard to find. There are few if any free alternatives.
The WinRing0 driver has some known security vulnerabilities. Some antivirus software might block this driver which will prevent you from using it.
Without Ring 0 access to the CPU, you will not be able to read any hardware related data from any of the model specific registers within the CPU.
Edit - Good news. I just did a search and found that the WinRing0 driver is still being maintained by German Aizek.
https://github.com/GermanAizek/WinRing0
You will also need Volume 4 of the Intel Software Developer Manuals. It lists many hardware registers but a lot of information is hidden from the public.
https://www.intel.com/content/www/us/en/developer/articles/technical/intel-sdm.html