What is Qadr? The Importance of Qadr (Predestination) in Islam
Before we were born, our souls were in a place called, "Alam-e-Arwah," or, "The Realm of Souls." There, we acknowledge Allah as our Lord. Our souls made friends in that realm, we were assigned our Qadr, Rizk and all of us accepted the divine decree but when we were brought into the physical realm of existence, we lost our memory of the previous realm.
The loss of memory occurs so that Allah can test who the best of us is. Our lives are already written for us. Most of us wonder if it is our Qadr to either go to Jannah (garden) or An-nar (fire)? We're all traveller in this world, heading towards Allah. Our destination is ONE but the means we choose to travel there is completely in our hands and that decides who ends up where, either in Jannah (garden) or An-nar (fire).
Summary
Qadr in Islam refers to predestination, where souls acknowledged Allah before birth and accepted divine decree. Upon entering this life, memory of that realm is lost to test who is best. Our lives are written, but the choices we make determine if we go to Jannah (paradise) or An-nar (fire).