Season the chicken with salt and pepper. Select sauté on the Instant Pot and adjust to normal. Heat oil in pot; add chicken and cook for 2 to 3 minutes per side until browned.
Add broth. Press cancel. Secure the lid on the pot.
Close the pressure-release valve. Select manual and cook at high pressure for 3 minutes. When cooking is complete, use a quick release to depressurize. Press cancel.
Use tongs to remove chicken to a serving platter; cover to keep warm.
Add lemon juice to cooking liquid in pot. Select sauté and adjust to normal. Bring to a simmer and cook for 5 minutes to reduce. Press cancel.
Whisk butter into sauce; add capers and parsley.
Pour sauce over chicken. Serve over pasta or rice. Serve with lemon slices.