You may need to install the wireless drivers if Windows' drivers are not picking up the onboard Wi-Fi. Do you have the ability to plug in the motherboard over ethernet for the time being to install these? If not, you could transfer the executable from another computer using a flash drive or similar method.
Check if the wifi card is presence in device manager, if yes it's more likely a software issue and might be resolved by uninstall and reinstall the driver, if not it's more likely a hardware issue.
You're welcome, please let us know if you have any other questions!
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