Is it permissible to work in a bakery that offers New Year's cakes and wedding sweets, and is that considered cooperation in sin and transgression?

Distributing sweets and gifts at weddings and happy occasions is permissible, and it is a well-known custom in Muslim countries.

As for New Year's cake, it is not permissible to make or sell it, because it falls under aiding in sin and transgression. The New Year's holiday is not one of the holidays of Muslims, and it is not permissible to celebrate it or to assist those who celebrate it. Congratulating disbelievers on their religious holidays is Haram (forbidden) by consensus, and it involves acknowledging the rituals of disbelief and being pleased with them. Similarly, imitating them by holding parties, exchanging gifts, or distributing sweets and food is forbidden, based on the Prophet's (peace be upon him) saying: "Whoever imitates a people is one of them."