Okay kiddo, do you know how some people talk different from others? In California, there is a type of talking that is different from other places. It's called California English.
When people talk in California English, they do some things different than other people. For example, they might say "like" a lot when they talk. So instead of saying "I went to the store," they might say "I, like, went to the store." Some people might think this sounds silly, but it's just how they talk!
Another thing in California English is how they say certain words. Like the word "water," some people say it with a "t" sound at the end, and in California English, some people might say it with a "d" sound at the end. So instead of "water," they might say "wadder". This is just how they learned to say the word!
Lastly, people in California might use different words for things. Like instead of saying "soda," some people might say "pop." Or instead of "freeway," they might say "highway." This happens because California has some unique words that aren't used in other parts of the world.
So that's what California English is, it's just a way that people talk in California that's different from other places. It might sound funny, but it's just how they talk and it's okay to talk however you want!