Is it permissible to distribute sweets to the cafes located in a mixed-gender university, and is that considered assisting in wrongdoing?

A servant of Allah should be keen on safeguarding his religion by avoiding the causes of temptation. And whoever works in a field that leads to seeing or hearing what Allah has forbidden will not be safe from it. Therefore, we advise you to look for another job that strengthens your faith, establishes your religion, and keeps you safe from temptations and trials, citing the words of Allah Almighty: "And whoever fears Allah - He will make for him a way out And will provide for him from where he does not expect."