Okay kiddo, so you know how when you want to go to your friend's house, your mommy and daddy usually have to say it's okay first? Well, countries are kind of like big houses and they also have rules about who is allowed to come in and visit.
Iran is a country in a special part of the world called the Middle East. In order to come and visit Iran, people from other countries usually need something called a visa. A visa is like a special permission slip that says you can go into Iran for a certain amount of time.
Now, Iran has different rules for giving out visas to people from different countries. Some countries are allowed to come in and visit easily, while others have to go through a lot of extra steps to get permission. This is called a visa policy - it's like their rules for giving out these special permission slips.
Iran's visa policy is a bit different from some other countries. They usually require people to have a sponsor in Iran - kind of like a grown-up who vouches for you and helps you while you're there. They also ask for a lot of extra paperwork and information, like your job, where you're staying, and why you want to come visit.
Sometimes, Iran changes its visa policy based on what's happening in the world. If they're worried about something, they might make it harder for people from certain countries to come visit, or they might ease up and make it easier.
So basically, the visa policy of Iran is just a set of rules that helps them decide who is allowed to come visit and what kind of permission they need to get.