Configure Azure Storage firewalls and virtual networks.
To secure your storage account, you should first configure a rule to deny access to traffic from all networks (including internet traffic) on the public endpoint, by default. Then, you should configure rules that grant access to traffic from specific VNets. You can also configure rules to grant access to traffic from selected public internet IP address ranges, enabling connections from specific internet or on-premises clients. This configuration enables you to build a secure network boundary for your applications.
Storage firewall rules apply to the public endpoint of a storage account. You don't need any firewall access rules to allow traffic for private endpoints of a storage account. The process of approving the creation of a private endpoint grants implicit access to traffic from the subnet that hosts the private endpoint.
Reference:
https://docs.microsoft.com/en-us/azure/storage/common/storage-network-security