Parts replacement after the collision

If I had a collision, lost a mirror of my car in it and waiting for insurance compensation. Ive never had accidents before, maybe anyone knows what happens after? The other driver is guilty. By rules I cant drive on the car without passenger mirror, but I dont know how long negotiations will take to be finished and when we get compensation. Can I buy the mirror by my own now and replace? Or In this case I will not get a money? Will someone check my car or my photos and videos enough?