Both destinations are served by Leh (IXL). Since there's no flight route between them, the best way to travel is by road.
Nubra Valley
Fly to Leh (IXL), then travel by road to Nubra Valley. Taxis, buses, and private cabs are available from the airport.
Ladakh
Fly to Leh (IXL), then travel by road to Ladakh. Local transport options include taxis, auto-rickshaws, and state buses.