Hey Laxmi, There is a bus from leh to delhi Bro ... And thats the cheapest you can get to travel from leh to Delhi .... HRTC has started a bus service and here is the link from Tripoto wanderer which h will help you in all means .... Please check this link and decide about how and when to book tickets and stuff ... https://www.google.com/amp/s/www.tripoto.com/trip/new-delhi-to-leh-ladakh-bus-service-by-hrtc.amp It takes time but will relish your experience for your life ... Happy Travelling Bro!!!