What is the ruling on holding mixed celebrations in a restaurant, knowing that they will bring alcohol with them and drink it in the restaurant's utensils that I purchased at my partner's request, and what is the ruling on me serving pork steak if a customer requests it?

It is not permissible to rent out a place to someone who will drink alcohol there or serve pork, due to the Hadith: "Allah has cursed alcohol, its drinker, its server..." and because pork is forbidden. The partner's statement, "If there is any sin, I will bear it," does not absolve the questioner, for Allah Almighty says: "And those who disbelieved said to those who believed, 'Follow our way, and we will verily bear your sins.' But they will not bear anything of their sins. Indeed, they are liars." For no one will bear the burden of another.