start outside and look for the external wall box - 6" square ish usually on wall facing road or pavement - brown or grey usually - follow any cables that come from it and go inside - if there are non look inside opposite external box as they may just have drilled through wall - as said it may just be a cable rather than an internal wall box
if you find a cable you need one of these to attach the cable that came with the quick start kit
Welcome to the forums and thanks for posting earlier in the week.
I'm very sorry to hear that you were both in the position of being unable to complete the self-installation of your new services.
I've been able to locate your accounts using the details you've registered to forums with and can see that you have been able to book engineers in for the issues via customer services, glad to see that.
Keep us posted and let us know if you require any future assistance,