Contract Formation: What About Mere Promises?

Kya mere promise se bhi contract formation ho sakta hai? I'm reading about the offer and acceptance, but what about jab koi mere saath mere future plans discuss karta hai? Let's say I promise someone that I'll buy a car from them in the coming year. No deal has been struck yet, bas mere promise hai. Is yeh mere offer ka koi value hai? Kya yeh contract formation ka step hai?

In India, Section 2(e) of the Contract Act says "An offer is the expression of a person's willingness to do something in consideration of any other thing being done or done." But, agar yeh mere promise pe depend karta hai, toh kaise aisa hota hai jab mere promise pe koi deal hone par nahin hota hai?