You could have 5 floors, and it still wouldn't be enough. You could have 30 floors and it wouldn't be enough.

I don't think you understand the scale of farming to human. Even if you're entirely vegetarian it's on the order of 0.5-1 acre per person to grow the required food. That's 20,000-40,000 square feet. Even if hydroponics were involved and cut that by a factor of 10, you'd still be at 2000 square feet per person. A typical grocery store is 25-50,000 square feet, so let's go with the most generous and say 5 floors of 50,000 square feet you could produce enough food for.... 125 people.

The math doesn't math. No reasonable amount of food growth is ever going to be possible inside a city.