@SudeepKumarReddyBalineni-1359
Currently you cannot whitelist inbound traffic from FQDN on NSG or Azure Firewall.
You can create IP group and add your IP's to that group and use in Azure Firewall(Ref).
Also, you can provide the feedback in feedback.azure.com for NSG or Azure Firewall, or upvote to this existing feature request of this ask here.
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