It would take you 15min to change it at most.
Once the car finds the fault fixed, it will then turn off the light and the system will go back to normal.
BUT, Im willing to bet that the airbag is not the issue, but actually the clock-spring. It is inside the steering wheel, and powers the airbag via contact strips since wires would break from turning. Over time these wear down, much like an alternator contacts, and the part needs to be replaced, it causes the car to not be able to communicate with the airbag thinking it has gone bad.