Brake lights

Most common reason for this is a defective brake light switch. Either the switch has failed or the pedal has an issue. To check, lift up on the brake pedal with the car off. Do the lights shut off? If yes you just need to adjust the switch. If they are still on you need to check a bit more. On the CRV there is a plastic button that goes in a hole on the brake pedal. If that piece breaks and falls out the pedal will not touch the switch, You can buy the factory part (expensive) or you can use a simple trim panel tree. Those are at most parts stores in the "help" section.

Now if neither of these is the problem it is likely that the switch failed. To replace the switch you unscrew the nut, pull it out of the bracket and remove the wire connector.

The switch is mounted behind the dash on a bracket so the plunger can contact the brake pedal. When you install the new switch make sure that the plunger is depressed when the pedal is up but you do not want it bottomed out. You install it with it all the way in, then turn it back 1/4 of a turn so it has a bit of play.

Here is a video on it, not a CRV but the same idea:
https://www.youtube.com/watch?v=NJQy7GT13Ao