After paterity test the father went for 3 months without any contact or support would that be considered child abandonment

Is there a standing court order on custody and placement? You can't force someone to visit if they don't want to; Wisconsin really doesn't refer to a parent's refusal to visit as "abandonment." However, if enough time goes by without any visitation, you may be able to involuntarily terminate their parental rights, if it would be subject to some type of adoption or step-parent adoption.