There are two countries, Greece and Turkey, next to each other. Just like how your bedroom is next to your sibling's bedroom. But sometimes siblings can fight and have arguments. Greece and Turkey are like siblings who sometimes don't get along very well.
They have a long border between them, kind of like the imaginary line that separates your side of the room from your sibling's side. This border is where Greece ends and Turkey begins.
Now, both Greece and Turkey want to make sure that they are safe and secure, just like how your parents want to make sure that you and your sibling are safe and secure. So sometimes they make rules and agreements about what can and can't happen along the border.
Sometimes, people who want to go from Greece to Turkey or vice versa need to cross the border. Just like how your sibling might need to come into your room to borrow something. But crossing the border can be tricky because both Greece and Turkey want to make sure that everyone who crosses is doing it in a safe and legal way, just like how your parents would want to make sure your sibling is following the house rules when they come into your room.
Thankfully, there are people called border guards who help make sure that everyone who crosses the border is doing it the right way. They check people's passports and make sure they don't have any dangerous things with them. They also make sure that no one is trying to cross the border illegally or without permission.
So, the Greece-Turkey border is like a line that separates two countries who sometimes don't get along very well, but who are both working hard to keep their people safe and secure. And just like how you and your sibling can find ways to get along and share your room, Greece and Turkey are also trying to find ways to work together and maintain a peaceful relationship.