Push saute feature on Instant Pot and allow for pot to come to pressure. When the pot reads hot add the oil and add onion. Saute for about 3-5 minutes.
When done, add chopped smoked sausage to the pot and stir. Saute for about 2 minutes.
Add milk, potatoes, sausage, frozen corn kernels, salt and pepper. Close lid and seal pot. Press the soup button and adjust time to 5 minutes.
When done, allow for a 5 minute natural pressure release. After 5 minutes, release remainder of pressure and open pot.
Push the saute button and add in 1 can of cream-style corn. Allow to boil/saute for about 2 minutes and serve.