Of course cats know their names. The only reason they don't come when called is that we have not always used it for good things.
Cats don't want to take a chance. Not only would that mean they would get a bad thing, like medicine or a bath, they also would feel betrayed.
We are supposed to use their name only for good things.
This is the easy way to train the cat to come when called.
If they always get a treat, a new toy, or some affection from us, they will want to come when they hear their name.
They like their name. We should never say it without a promise in our voice.
Read more about how cats learn their names.