What is The first thing to do when changing the battery or refueling?

The first thing to do when changing the battery or refueling is to ensure safety by turning off the vehicle and removing the ignition key. For battery changes, you should also wear protective gloves and eyewear to guard against acid spills. When refueling, make sure to turn off any electronic devices and avoid smoking or using open flames nearby. Always follow the manufacturer's instructions for both tasks to prevent accidents.