cereal already?

Ni

FTM here, My baby boy is 2 1/2 months old and is eating more formula than recommended he's eating 5-6 ounces every 2 1/2 to 3 hours...i was wondering if anyone has started their baby on cereal already at this age or even other food to keep their baby more full? I feel like it's not satisfying him and that he wants more.