1. Is it permissible to recite Dua E Hifz E Iman (Razi to billah E Rabban) in Qunut in Wajib & Mustahab Namaz?

2. Also what is the meaning of taslim in Shab Namaz?

3. In Nafilah Namaz which is of more than 2 rakats, qunut is to be recited after every 2 Rakats?

1. Yes
2. Taslim is the same as salaam to end the prayer
3. Every nafilah is 2 rakat. Where more than 2 rakat is mentioned the prayer must be done in sets of 2.