It depends on how the extension socket in the front room is wired.
What kind of socket do you have in the kitchen, does it have two outlets on the faceplate ?
If so, the extension is probably wired as a "phone only" on the back of the faceplate so no internet devices will work on any extensions.
TT have sometimes supplied powerline adapters to enable TV boxes to be connected in other rooms so please fill in your community profile with your name, address and TT landline number and await a reply from a staff member, do not post the info here in public.
