Hi Magirish
Welcome to the forum.
You might want to have a look at the following FAQ which explains where everything is;
www.benefitsandwork.co.uk/guides-for-claimants/faq/forum.
It will confuse things, if you can set up a new email for your son it will make things easier, as for your phone number, DWP are using more and more AI technology, having the same number may cause you issues, I would have a discussion with UC helpline.
Gary
