Can someone live without their legs and arms?
People already do.
yes, they do now. :/
Yes, long time ago the US Government Oked a drug called thalidomide. It caused a lot of birth defects like you mentioned. The kids adapted, it was a sad incident though.
All the time. Not that it's easy but you do what you gotta do.
Sure they can
Yes. It's the head that is a little difficult to live without.