Set Instant Pot to Sauté mode and preheat before adding any oil. Add olive oil, and then the onion and garlic. Cook, stirring, until softened, and translucent, about 3 minutes. Deglaze with a splash of water or stock to prevent anything getting stuck to the bottom and BURN warning.
Next add the tomatoes and chicken stock and bring to a boil. Stir to make sure nothing is stuck to the bottom.
Add orzo, dill and parsley and mix well.
Next shrimp and season with salt and pepper. Add feta cheese over the top.
Set Instant Pot on Manual High Pressure for 3 minutes.
Once done, use Quick Pressure Release to avoid overcooking orzo and shrimp.