What is the ruling on working in a restaurant during the month of Ramadan, knowing that the nature of the work includes delivering orders and helping to serve them to customers inside the restaurant?

It is not permissible to offer, sell, or deliver food during the daytime in Ramadan (definition) to anyone who would eat it, whether Muslim or non-Muslim. A Muslim is obligated to fast, and a non-Muslim is addressed by the branches of Islamic law. It is not permissible to assist anyone in breaking their fast, for Allah Almighty says: "And cooperate in righteousness and piety, but do not cooperate in sin and aggression" (Quran 5:2). As for those with legitimate excuses, such as the sick, the traveler, or the menstruating woman, it is permissible to offer them food, but they should not openly eat in public places.