Before indulging a family cat to the wide variety of foods in a home, consider what is good and what is dangerous. Dog food is a no-no, for example. There are human foods that cats can eat. There is a list of absolutely forbidden ones, as well. Any food not specifically formulated for cats can affect their digestive system, causing vomiting, diarrhea or loss of appetite.
. . . foods of concern include; alcohol, coffee, tea, energy drinks, and chocolate, which is bad for cats.
Source: Tufts Catnip, March 2019. Link.
According to Cailin Heinze, VDM, DACVN, . . . cats (and dogs) should receive no more than 10% of their daily calories from treats or snacks. . . Tiny pieces of vegetables and fruits can provide a low-calorie healthy snack.