My son has a 2 yr child to his ex girlfriend.she now has another child to her new boyfriend.what happens if he adopts my grandson.can my son still see him and do we as grandparents have any rights to see him

What state do you live in? Some states recognize Grandparent rights and some do not have that yet. Especially with adoption, you should really speak to a family law attorney.

I got your email and that you live in England. I wish I could help you but I know so little about the laws there. What applies here, in the U.S. may not there. Hopefully a member of the forum, who resides in the UK, will see this and respond to you. Outside of that, at least call a barrister there and ask. Best of all to you.