Here is the simple summary for how to throw passes in Backbreaker. To select a receiver to throw too, hold Left Trigger, which makes your player focus on a receiver. Once in the focus mode, you can use the right thumb-stick with a left or right movement to cycle through the receivers. Passing is also done with the right thumb-stick. There are two main passes, the bullet pass and the lob pass. To throw a bullet pass, simply move the right thumb-stick strait forward and the quarterback will throw a bullet pass to the highlighted red receiver. To throw a lob pass to the receiver, quickly go back on the right thumb-stick and then forward. Do not hold the thumb-stick back, do it in one fluid motion, back to forward.
Here is the video showing how to throw a bullet and lob pass in Backbreaker by 505 Games.