How many grafts will it take? I am 29 years old (photo)

You have a pattern of balding that indicates that you will probably lose all of the hair on the top of your head, maybe the frontal forelock will remain, maybe not. Based upon your skin color, I suspect that you may have an Indian heritage which means to me that your donor supply will be lower than the donor supply of the typical Caucasian. Your doctor needs to build a Master Plan with you, measure your donor hair density and donor supply for the long term. This will determine not only what you need now but what you will need in the future as well.  I suspect the first surgery will take at least 2,000 grafts and further surgeries in the next few years may be required as you lose the rest of the hair on your head. I also suggest that you consider taking the drug Finasteride to protect the hair that you have left for both the short and long term.