You will need to open all the walls to the roof that surround the chimney.
You will need to remove the chimney from the roof to the first floor.
Close the roof off and shingle to match the current color.
Reframe the walls opened for demo.
Possibly reframe the floor and ceiling joists.
Add matching flooring if needed.
Paint all the new sheetrock(maybe the rooms)
Have all the brick and mortar carted away.
Realize that removing a houses asset will reduce the value somewhat.