What is the outlook for a child diagnosed with pulmonary atresia (pa)?

Fairly good. They will require surgery as an infant to establish pulmonary blood flow. At some point a pulmonary valve replacement will be needed. Patients have some limitations on strenuous activity, but attend school, can work and have children.
Depends. There are different forms of pa. If the right ventricle is of good size (either because of a hole in the ventricular septum or due to tricuspid regurgitation) it can be repaired with a good long term result. If the right chamber is too small surgery is more complex and life expectancy reduced to the 4th decade. If pulmonary blood flow comes through multiple sources it is even more complex.
Depends. Depends on whether there is also an intact or open ventricular septum (vsd) and how quickly and effectively the pulmonary valve can be opened after birth, if necessary. There's no good "one answer" to this question without a lot more information about the specific case.
Depends. That diagnosis is significant. The child will certainly require at least surgical procedure to establish blood flow to the lungs. Long term prognosis depends on whether surgeons can maintain two ventricles, if there are other medical conditions etc. Please see your child's cardiologist to discuss your specific issues.
Surgery. The doctors will try to keep the ductus arteriosus (the temporary connection between the body and lung blood flow) open until the baby is ready for surgery.