An internet challenge is like a game that people play online. These games can be fun, but sometimes they can be dangerous too. Some challenges are easy, like a puzzle or riddle, while others are more difficult and might require you to do something unusual or even dangerous.
For example, you might have heard of the "Ice Bucket Challenge" which was a popular challenge a few years ago where people poured a bucket of ice water over their heads to raise money for a good cause. But there are also more dangerous challenges like the "Tide Pod Challenge" where people ate laundry detergent pods which can be harmful to your body.
It's important to make sure that if you're going to participate in an internet challenge, it's safe and doesn't put you or others in danger. Always talk to an adult first and make sure you understand the risks involved before participating.