This question already has an answer here:
As I understand it, boiling takes place when the saturated vapour pressure equals to the atmospheric pressure.
But, why does the vapour pressure need to be equal to the atmospheric pressure for water bubbles to form?
According to this video, the atmospheric pressure is cancelled by the vapour pressure at boiling, which allows for the bubbles to form (due to the zero total pressure).
But, I think the atmospheric pressure is the same. So, if we consider the atmospheric pressure to be 1atm at a time, the surface of the water feels 1atm pressure every time (I mean that atmospheric pressure is 1atm as same as the before, but the vapour pressure and the air pressure is acting as a partial pressure according to Dalton's partial pressure concept, it doesn't affect the total atmospheric pressure.)
So what is the real reason?