Yogurt_ Halal or not?

It contains gelatin. It is usually made from pig or cow. In Korea, cow normally is not slaughtered based on Islamic law. I suggest to avoid it.

its haram beceause has gelton

The major source of gelatin is pigskin and as in Islam; it is not acceptable because it is Haram. But if it's made by heating (Cow/Sheep/Goat/Camel/Buffalo) milk and combined with two live cultures (Lactobacillus bulgaricus and Streptococcus thermophilus) then it is considered halal. Cow milk is mostly used. So It does matter if the cow is not being slathered. But the cow or the animal needs to be fed organic foods. Only then the milk can be halal.

What is gelatin called in korean please ? So i can check the ingredient myself

As far I know, the gelatine in Korea is 젤라틴. I don't if there is another name.