No. Most systems in a ICE car are designed to be run off the belt of an idling engine. An electric car is only running when you put your foot on the accelerator

No. Most systems in a ICE car are designed to be run off the belt of an idling engine. An electric car is only running when you put your foot on the accelerator. So cooling, climatisation, power steering, braking assistance will all need an electric retrofit in addition to the drive train. Ford tried to retrofit an electric PHEV in its Escape and Fusion. Most of the useful cargo space was taken away to retrofit the relatively small battery.