Disclaimer - I don't work for Virgin Media. I'm just another VM user trying to help out. My setup: V6 TV box, M350 Fibre broadband with Hub 3 in modem mode connected to a Netgear R7000 router. Telewest/VM user since 2001.
As a Very Insightful Person, I'm here to share my knowledge. I don't work for Virgin Media.
Re: Is it possible to create a VLAN with not internet access ? (For Ip camera)
I can't help thinking that VLANs are probably not the way to go here. Firstly VLAN tagging is something that's better suited to a switch than a router and presumably you would want the cameras to talk to something even if it's a phone/tablet on your own network. So unless the phone etc. is on the same isolated VLAN, you'll need some kind of inter VLAN routing, which requires (ideally) a managed, layer 3 switch and you'll need to configure the access control lists to block unwanted traffic. It'll all get very messy and complex (not to mention expensive) quite quickly.
You'll definitely need to get your own router but it'll probably be easier to set a fixed IP address for the camera (personally I prefer doing this with reserved DHCP addresses) and then having some outbound firewall rules which drops traffic from the camera's address to the internet. Don't bother too much about DNS, if the camera was calling home it'll almost certainly be doing it to a hard wired set of addresses anyway.