As you apply the foot brake, the pedal goes to the floor. what should you do first?

If while driving, you apply the foot brake and the pedal goes to the floor, it’s an indication of a failed brake. In such a case, the first thing to do is to shift to a lower gear. The second step is to pump the brake pedal fast and hard two to three times in order to build up brake fluid pressure. The third step if the brake still doesn’t respond after step 2 is to use the parking brake.