بسم الله الرحمن الرحيم
(Fatwa: 379/330/SD=4/1439)
Yes, it is mandatory to make qaza of all the fardh or wajib (witr) prayers and all the fardh fasts which you missed after calculating them; otherwise it shall remain due on you. It is not enough to make taubah and pay fidyah.
Allah knows Best!
Darul Ifta,
Darul Uloom Deoband
