Extract juice from oranges and tie pips and piths in a muslin cloth.
Cut the peel very thin and soak it in water overnight.
Now turn on the instant pot and add juice, peels, water and muslin cloth in it.
Set the instant pot to “Manual” at high pressure for 15 minutes, release the pressure naturally through steam vent.
Squeeze all the juice into the pot from the cloth and discard the cloth.
Add sugar and heat gently until it dissolves.
Heat it and let it to boil until the marmalade is reached to a setting point.
Store it in jar and enjoy.