I don't think we're adaptable enough to survive without food. Collapse of the food chain have happened on Earth before humans and is among possible consequences

I don't think we're adaptable enough to survive without food. Collapse of the food chain have happened on Earth before humans and is among possible consequences of climate change. Same with breathable air, how would humans adapt to an athmosphere composition without oxygen as happens when earth magnetic field is weaken during geomagnetic reversals ? My point is we are facing an ongoing mass extinction event and based on current knowledge of previous events humans being wiped out is a possibility. Based on the number of species that are extinct, extinction is not that hard specially during a mass extinction event.