Add olive oil to Instant Pot and press SAUTE button.
When screen reads HOT, add chicken pieces and season with salt and pepper.Cook 2 minutes, turn, season again and cook 2 minutes more.Press CANCEL. Sprinkle packet of taco seasoning over chicken, pour water over it and top with salsa. DO NOT STIR!
Lock on lid, turn pressure valve on lid to SEALING.Press PRESSURE COOK button and adjust timer to 10 minutes. When time is done , allow the timer to count up for 10 more minutes of natural pressure release. Press CANCEL.Turn pressure valve on lid to VENTING to release any remaining pressure.Open lid and remove chicken pieces to a plate. Press SAUTE button and cook down liquid left in pot while you shred the chicken.To shred chicken you can use 2 forks or for a faster method use your electric mixer (just place in bowl and run at medium speed until meat is shredded). Return the chicken to the Instant Pot and give it all a good stir.Press CANCEL.Use immediately as filling for your hard and soft taco shells, or let sit in pot to stay warm until ready to serve. Set up your condiments and toppings and warm your taco shells to serve along with the chicken.