If a father has not seen his child in 6 months or had any contact how can I file for abandement

No. There is this total misconception on abandonment. Except in a very few states, you can't file for abandonment. You MAY be able to use abandonment as grounds for something else. So you really need to define what you really want.

So what are you wanting, first this is not criminal, it is a civil family court issue, you can claim it, to ask for changes in custody, changes in visititation orders.

So you claim it by hiring an attorney to file new motions in family court