How to add or remove Network Interface from VM in Azure

Add a network interface to an existing VM

1. Sign in to the Azure portal.
2. In the search box at the top of the portal, type the name of the VM to which you want to add the Network Interface, or browse for the VM by selecting All services, and then Virtual machines. After you've found the VM, select it. The VM must support the number of network interfaces you want to add 
3. Select Overview, under SETTINGS. Select Stop, and then wait until the Status of the VM changes to Stopped (deallocated). 
4. Select Networking, under SETTINGS. 
5. Select Attach network interface. From the list of network interfaces that aren't currently attached to another VM, select the one you'd like to attach. 

6. If you don't have an existing network interface, you must first create one. To do so, select Create network interface.

7. Select OK.

8. Select Overview, under SETTINGS, and then Start to start the virtual machine.

Remove a network interface from a VM

1. Sign in to the Azure portal.
2. In the search box at the top of the portal, search for the name of the VM you want to remove (detach) the Network Interface from, or browse for the VM by selecting All services, and then Virtual machines. After you've found the VM, select it. 
3. Select Overview, under SETTINGS, and then Stop. Wait until the Status of the VM changes to Stopped (deallocated).
4. Select Networking, under SETTINGS.
5. Select Detach network interface. From the list of network interfaces currently attached to the virtual machine, select the network interface you'd like to detach. If only one network interface is listed, you cannot detach it, because a virtual machine must always have at least one network interface attached to it. 
6. Select OK.