Check the fuse in the fuse box.
If the fuse is bad, check or replace the brake light bulb.
If the brake lights are intact, check the brake light switch, which is located on the bracket above the brake pedal. When you press the pedal, the push pin comes out of the switch. The switch contact closes and the brake light comes on.
To test the brake light switch, disconnect the two cable connectors from it.
Turn on the ignition.
If the brake light comes on when the jumper closes both pins of the connector, then the brake light switch is faulty, it must be replaced.