My husband wants to adpot my daughter who is nearly 6 and hasn't seen her father since she was 2 he didn't want contact with her after that her father and I were never married or togetor when she was born how would we go about doing this

Get a lawyer.

Make an earnest attempt to get in contact with the child's biological father to sever his parental rights to make way for an adoption.

Have adoption papers prepared and processed through a court.

But... your first and most important step is to get a family lawyer.

Yes, you will need to see an attorney and get them to work on the paperwork. But an attempt to find the bio father will have to be done and an attempt to get him to sign over his rights. Assuming he has been paying or should have been paying child support, he should be glad to sign over the rights since he his child support payments would stop then