@Guilherme Dos Santos Soares, Thanks for posting in Q&A. After researching, I don't find a method in Intune to block one specific Wi-Fi in Intune. But in Android Enterprise Dedicated enrolled device, it has an option 'Wi-Fi allow list" to set allowed connect Wi-Fi.
https://learn.microsoft.com/en-us/mem/intune/configuration/device-restrictions-android-for-work
You can check on Wi-Fi provider to see if there's an option to do MAC mapping which can only allow some specific devices to allow access.
Hope the above information can help.
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