Earth cannot have a magnetic field without inner and outer core rotating with relative to each other. The way this happens is the both cores would have to be spherical with an inner core inside a hollowed outer core. Otherwise we would be literally get fried by the sun.

The only physical way for this to be possible is if the whole planet and it’s sub structures like crusts and mantle were ALSO spherical.

The empirical evidences are vast for globe earth yet flat earthers only have YouTube videos as references lol