Put the rice in the Instant Pot and add the water. Shake the coconut milk and measure 1 cup; add it to the Instant Pot along with the salt and stir to blend.
Lock the lid in place and make sure the vent is in the sealing position. Some pots are automatic. Choose pressure cook (or manual), high pressure, and set the time for 22 minutes. It will take approximately 10 minutes to come to pressure.
When the time is up, let the pressure come down naturally for 10 minutes. Carefully release the remaining pressure.
Fluff the rice and stir in the cilantro and green onions.