It would be "Doctors Without Borders" that functions to provide clinics and surgeries in developing nations, although it should be noted that other organizations such as the International Red Cross help fund these efforts.
The organization that functions to provide clinics and surgeries in developing nations is Doctors Without Borders. This organization constitutes and independent, global movement that provides medical aid where it is needed most. It provides lifesaving medical humanitarian care. It was created in 1971 and has treated tens of millions of people since then.