Food is chemical energy stored in bonds, primarily between carbon and hydrogen and carbon and carbon, which metabolism converts into electrical energy and then into ATP.

“food is chemical energy right so you have you eat these things and they have Bonds in them they have you know especially hydrocarbons right they're incredibly rich in stored potential energy within the carbon carbon and carbon hydrogen bonds in particular these are the most energy rich bonds metabolism is a fancy word for taking the chemical energy that is stored within the bonds again primarily between carbon and hydrogen and carbon and carbon and turning that into electrical energy and that electrical energy is used to turn back into chemical energy so you take the electrical energy in the electron transport chain for example and then you shuttle it back back into chemical energy in the form of ATP”