If you call a restaurant, and order food for delivery, Should you be able to cancel your order even if they started making the food?
Can I have a answer and sources please.
Answer:
If the food can be sold to another person, you would be exempt from paying. If the food will go to waste and they will suffer a loss because of your order, you would be responsible to pay.
Sources:
Shulchan Aruch C:M 333:8, based on Teshuvos HaRosh 104:6, who considers this a case of "garmi", direct causation of damages which obligate pay. Hence, even though there was no hiring of a worker [as per C:M 335:3], as ordering food is an agreement to pay for the finished product, there is still an obligation to pay.