Pour Milk directly in your instant pot. This does not require pot in pot. Place your pot on “Yogurt” function and hit the adjust button until you see ‘Boil’. Place lid on and in venting position. Allow to complete the boil cycle about 30-40 minutes. Check temp of your milk, it should be 180 degrees. Remove pot and set it on the counter. Stir in salt. Cut your lemon in half and squeeze the juice from each half into the milk. Let mixture sit for 15-20 minutes until you see the whey start to separate from the milk. Place a mesh strainer over a bowl and pour the mixture into a mesh strainer. Let mixture drain about 20 minutes. If you do not have a mesh strainer you can use a regular strainer with cheese cloth, or coffee filters. Refrigerate up to 5 days in an airtight container.
If you do not have an instant pot you can make this on the stove over a medium heat bring your milk to almost a boil at 180 degrees.