Remove the core from your apples. Leave the skins. They will be removed later by the food mill.
Place into the pot of your Instant Pot, making sure to not fill them above the maximum fill line.
Add ⅓ cup to ¼ cup of water to just cover the very bottom of the pot, so that the apples don't stick to the bottom
Set your Instant Pot to high pressure for 5 minutes.
Allow to naturally release.
Open the lid and allow the sauce to cool for 5 minutes.
If you have peeled the apples and the sauce is too chunky, you can use a immersion/stick blender, hand blender, or potato masher to smooth out.
After you are done with the food mill, If you think your applesauce is too thin, set the Instant Pot to sauté and reduce some of the moisture in it. Be sure to stay nearby and stir often until desired consistency.