Complex sentence: Most of the passengers originated from Paris, who boarded Yemenia Flight 749, operated using an Airbus A330-200, with a stopover at Marseille Provence Airport in Marseille, France, where some more passengers and crew boarded.
Split into simpler sentences: Most of the passengers originated from Paris, who boarded Yemenia Flight 749, operated using an Airbus A330-200. There was a stopover at Marseille Provence Airport in Marseille, France, where additional passengers and crew boarded.