Season the chicken with salt and pepper. Add the carrot, celery, chicken, rice and broth to a 6 quart Instant Pot®.
Lock the lid and close the pressure release valve. Pressure cook on High pressure, setting the timer to 5 minutes (timer will begin counting down once pressure is reached- it takes about 15 minutes). When done, press Cancel and use the quick release method to release the pressure.
Remove the chicken from the pot. Shred the chicken and return to the pot. Season to taste.