Okay kiddo, let me explain to you what critical security studies means.
You know how sometimes people might feel scared or worried about things like getting hurt or someone taking their things? That's something called security. And sometimes people have different ideas about what kinds of things are the most scary or dangerous.
Critical security studies is a way of looking at security and trying to understand why some things are considered more scary or dangerous than others. Sometimes, people in charge (like government leaders) might say that certain things or groups of people are a big threat to security, but not everyone agrees with them.
So, people who study critical security studies try to ask questions like: who gets to decide what's a security threat and why? How much power do those people have? How do their decisions impact different groups of people?
Overall, critical security studies is about trying to think more carefully about how we talk about and try to protect ourselves from different kinds of scary things, and making sure that everyone's needs and perspectives are taken into account.