As to the first question of parenting rights: An unmarried father has no parenting rights outside of a custody order. You are not required to let him see the children until he gets that order.
As to the adoption, it is possible to obtain a step-parent adoption without the father's consent (and this mostly happens when they do not contest the proceeding) but if they do contest the proceeding then it is extremely difficult to have the children adopted by another person. Even gross neglect and cruelty can be insufficient.
Answered on Jun 23rd, 2020 at 10:01 AM