Login to you Azure Portal and locate the storage account you wish to prevent access to via http
Click configuration from the left pane, and then from the right pane, switch Secure Transfer Required to enabled, and click save
If you wish to secure your storage account further, lock down your storage account so only certain networks are able to access it. The default setting is All networks (including the internet, can access this storage account)
To lock down your storage account to a particular VNET or even a IP address, click Firewalls and Virtual Networks from the left pane
Click selected networks, and then click the link + Add existing virtual network, or if you wish to lock down the storage account to an IP address, scroll down a little further within your Azure Portal
Select your VNET, Subnet and click enable
