Is there where to have breakfast?

If there are some options according to taste, inside the building when entering.

Yes, there is. There are several options inside the Willis Tower. There's a food hall overlooking the first floor atrium with options including "Shake Shack", "Brown Bag Seafood Company", and "Do-Rite Donuts &Chicken". There's also an option for breakfast, lunch, or dinner on the skydeck ledge catered by "The Metropolitan". The Metropolitan is where members dine with chores of the city.

Outside yes. Inside I don't remember

So