my son and his girlfriend had a baby and cant afford healhcare we want to put child on our insurance what has to be done to do this

First you should find out about New Jersey Family Care which may be able to help.  Next contact your health insurance and complete the application forms. Your son can go onto your insurance if he is the right age, you might also be able to include your grandchild.  If not, I believe the child would be eligible for NJ family care.