So, you know how sometimes when you play with your friends, your mommy or daddy might say that you can only play in your own yard or house? Well, think of Gaza as a big yard that lots of people live in.
But instead of your mommy or daddy setting the rules, there are some other grown-ups who set the rules for Gaza. These grown-ups don't want people to go in or out of Gaza very much. They don't want things like toys or food to arrive easily.
This is called a blockade. It's like saying "No, you can't bring that toy into my yard" or "You can't go to the store to get more snacks".
The people who live in Gaza are not happy about this because it makes their life harder. Sometimes they can't get things they need for their homes or families. And sometimes they can't leave Gaza to visit other places or see their friends or family.
It's a complicated situation and different people have different opinions about it. But in the end, it means that the people who live in Gaza have to follow certain rules and can't always get or do what they want.