Make the bruschetta topping, in a bowl combine tomatoes, red onion, garlic basil, lemon juice, salt and pepper. Stir and set aside.
To the instant pot, add the chicken, italian seasoning, salt, pepper, olive oil, and diced tomatoes. Give everything a good mix.
Add the pasta so it’s on top of the chicken, then add water (the water should cover the pasta, or almost cover).
Secure the lid of the Instant Pot and make sure that the vent is in SEALING position. Select the PRESSURE COOK/MANUAL setting and set the cooking time for 3 minutes at high pressure. The Instant Pot will take around 10 minutes to come to pressure and start cooking.
When the cooking program ends, quickly release the steam and remove the lid.
Give everything a good stir (the pasta will absorb most of the water). Add parmesan, and bruschetta topping, stir well, cover with a lid and let it sit for 5 minutes. Garnish with extra fresh basil and parmesan before serving.