If none of the above helped, scan your system for integrity violations.
To do that right-click on the adapter > click Update driver > Search automatically for updated driver software. If instead, it is something like Parallels Ethernet Adapter #., it means the driver was installed incorrectly and needs to be updated. It should be identical to the name in the virtual machine's configuration ( the virtual machine's configuration > Hardware > Network > Type). In Device Manager go to Network adapters tab and expand it.
Perform clean boot in Windows by disabling 3rd party applications' services including 3rd party antivirus software which may have a negative impact on a network driver's installation.Before going any further please take a snapshot ( Actions > Take Snapshot) to revert to a pre-troubleshooting point.Make sure your Mac is connected to the internet, Windows will not be able to access the internet if it's disconnected or inaccessible on the Mac side.Virtual machine's settings misconfiguration.3rd party applications or antivirus software are blocking network connection.Network settings misconfiguration in Windows.
Other home network computers are not reachable.Issues with network dependent software even though the internet in Windows is working fine.Internet connection is low or unstable.No internet connection in Windows, however internet is accessible on the Mac side.