Ill add this.
Oswald worked in that building. He was familiar with the plaza, the sight lines, everything. This was not “foreign territory” for him. He didn’t have to GO somewhere to do the shooting. He had SOME amount of time to think about and plan those shots. That’s why people think he hit with the first shot. However, the THIRD shot was the most precise shot. Why? Couple of reasons. First, he could adjust his aim after missing the head with the first two. Second, the motorcade slowed down bc the driver turned backwards to see what was happening. He can’t speed away if his head is turned looking back. Lastly, by the time of the third shot Kennedy is in the open. The tree is no longer an obstruction.
Oswald has the benefit of readjusting his shot, the car is slowing down and Kennedy is the open. The third shot was the easiest.