Which type of Biryani are you interested in making? There are lots of different types - Hyderabadi, Dum Chicken, etc.
There are tons of recipes on-line; Biryani is one of my favorite things in the world to eat, but it is quite labor-intensive if you do it right. I've been an assistant to Biryani-making sessions and it takes two days! These were family recipes where the spice-blends are homemade.