Avoid mentioning the Omegle site by name unless your child mentions it; if they’re not already aware of the site, it’s perhaps best that it stays that way.
Instead, aim to speak openly and honestly with your child about chat sites in general and the many risks that can be present when talking to others online. Discuss (in an age-appropriate way) that sadly there are some people who use chat sites to get to know others for the wrong reasons. Omegle promotes the concept ‘Talk to Strangers’ as its selling point; this is something we should be continuously educating children about and the related risks.
Talk about information that is personal and private, reminding children that anything they share can be recorded or copied, then forwarded or shared with others.
Discuss online etiquette and issues relating to cyberbullying, in general terms, relating to all social media and interaction networks. Try to be supportive and non-judgemental so that your child feels they can approach you as their trusted adult should they have any online concerns.