How doctor would respond to him patients. how do cells repair themselves? what are the different organelles that make up our cells? what are their functions?

Cells can repair themselves in a molecular level through its DNA and the process involve, either the old damage cells are renewed and resynthesized by new ones as cell divides and undergoes such division.

Organelles are tiny parts of a cell, in analogy are like organs. They perform various tasks vital for a cell to survive. They deliver information, send nutrients and excrete waste and protect cells from antibodies and other microorganisms that could and possible harm the cell itself.
Cells repair themselves through the process of cell division and mitotic process. Mitosis occurs more in your body since it changes, modifies and requires cell division at maximum rate in many useful situations with the stand to a particular system and organ. Mitosis and meiosis are simply cell division processes that occurs differently, they're characteristically divergent from each other according to their function and structure. 

They must use the scientific method

Yes yes yes very good