Although it is common knowledge that water boils at 100 degrees Celsius (and 212 degrees Fahrenheit), it isn't quite intuitive that water can't really surpass that temperature if heated more.
[This is obviously only considering normal circumstances]
Boiling point only really serves to mark the point where water has enough energy to transition from a fluid to a gas state.
Thus no matter the temperature you've set your stove, if the water's boiling, it'll always be at just around 100 degrees Celsius.
The exact temperature will however vary. This is due to factors such as altitude where a higher one will equate to a lower boiling point.