Question: Is it possible to get internet access and a unique ip address as well in kali linux Vm. If yes, then what would be the networking configuration?

Answer: 
Yes, just make sure you set the network adapter as bridged, not as NAT, and the VM will become part of your network, getting its IP and internet access from the router (or whatever does DHCP and routing)
Without more details, it’s very hard to explain what you want.

Virtual box creates a virtual machine environment on top of your host operating system. It has several options for how to configure networking.

If you select bridged networking, then your virtual machine is effectively on the same LAN or Wi-Fi as your host with different/Unique IP. It will talk to an external DHCP server and get external information.

If you select ‘shared’ networking, then your host will provide a virtual LAN for the VM to reside on, with the host providing routing and NAT services to the outside world. Your host will also provide DHCP services on the virtual LAN.

And then, it gets complicated…