Self-surgery is when someone tries to fix a problem with their own body without the help of a doctor. This can be very dangerous because doctors have special training to know how to fix and treat different problems in the body.
Imagine you have a boo-boo on your finger and there's a little piece of glass stuck in it. You might think it's a good idea to take out the glass yourself, but it's not safe. You could make the boo-boo worse by cutting yourself more or getting an infection.
It's important to always ask an adult for help if you hurt yourself or if something doesn't feel right in your body. They can take you to a doctor who can help you feel better and fix the problem safely. In a medical emergency, it's important to stay calm and call for help right away.