Microsoft’s driver is a stripped-down version. Installing the full Realtek “verified” installer replaces it with the feature-rich version.

You don't need to be a programmer to verify a file. Here is the manual check for absolute safety.

Ethernet not working and weird file showing up. - Microsoft Q&A

Run this as Administrator:

If Windows blocks it, you may need to disable or the Vulnerable Driver Blocklist via Registry Editor. Best Practices

Your PC may have an Intel or Killer NIC instead of Realtek. Check Device Manager again. If it is indeed Realtek, try updating your motherboard BIOS—older BIOS versions may not report the NIC correctly.