What is the ruling on eating meat slaughtered by non-Muslims, especially atheists, given doubt about the method of their slaughter, and what is the ruling on using eating utensils shared with them?

It is not permissible to eat the slaughtered animals of disbelievers other than the People of the Book, nor anything mixed with it such as broth. Allah has permitted us only the food of the People of the Book. As for fruits and the like, there is no harm in them. The food of Muslims is lawful for Muslims and others if they are truly Muslims. Muslims must have their own utensils, and if they cannot find them, it is obligatory to wash the utensils of the disbelievers before using them, in accordance with the Hadith of the Prophet, peace and blessings be upon him.