It could be a fake news story, information that is not true or a fake website. Or someone could pretend to be another person online.
Look for clues that something is fake. Ask lots of questions. Get your info from lots of different places online. Look for signs someone may not be who they say they are.
If you think something or someone online is fake, ask your mum, dad, carer or an adult you trust.
You can read more about this topic.