What is the ruling on working as a food delivery driver for restaurants in Europe, without knowing whether the restaurant is halal or not before signing the contract, given that the person is in debt and cannot repay it except through this part-time work?

The basic principle regarding food delivery is permissibility. However, if the order contains prohibited food, it must be abandoned, and it is not permissible to assist in consuming what is unlawful. If the questioner can avoid delivering prohibited items, there is no harm upon him. But if he cannot avoid it except by delivering all orders (both permissible and prohibited), then he must leave the job and seek another, unless he is in a state of necessity. In such a case, he may remain in the job but must dispose of the earnings from the prohibited deliveries by giving them to the poor, unless he himself is in need of them. As for the matter of debt, it is considered a necessity if it leads to imprisonment, unbearable hardship, or inability to secure the minimum necessities of life.