Does subchondral insufficiency fracture of the superolateral aspect of the left femoral head require a surgery? or will bed rest help?

Not bed rest.: Your question suggests a diagnosis called avascular necrosis which means you have lost blood supply to a portion of the bone in your hip. Bed rest will cause more problems than it will solve but using crutches and partial weight bearing may settle down the symptoms and allow some healing. If symptoms aren't manageable with medication and relative rest, you may require a surgical procedure.