KLM Royal Dutch Airlines
KLM Royal Dutch Airlines Travel documents
Summary
Your passport must be valid for the entire trip, and Indian passport holders generally need a Schengen visa to enter the Netherlands. Airside connections through Amsterdam Schiphol usually don't need a transit visa, though some multi-Schengen-layover or US-India routings can require one — check KLM's travel documents tool for your specific itinerary.