when can qaza be prayed?
Once you arrived at the figure , start praying your wajib salat and after every salat - FAJR ZUHR ASR MAGHRIB ISHA , pray your qaza prayer. Example pray 2 fajr one wajob & the other as qaza. If u are 30 years and have not prayed from age of 15 to 20. 5 years qaza.