If the natural father has not been in the child's life , never supported. Do I still need his consent for step parent adoptions?

The court will require that you, at least, try to obtain the father's permission.

You will need to contact him, or at least try to find him if you do not know where he is. If he refuses to sign, you can still try, ( he most likely will not show up in court to fight it)
So it is possible, but much harder if he will not sign.