I don't understand the correct meaning and concept of the following sentences.
1. I can't hear what are you saying?
2. I can't hear what you are saying?
another example;
1. Where are you going?
2. Where you are going?
In your first block, example 2 is normal usage: "I can't hear what you are saying?" while example 1 would only be normal if you inserted a comma: "I can't hear, what are you saying?" Both have essentially the same meaning, which is largely "Speak up!"
In your second block, it is the other way around: "Where are you going?" is normal usage, and I can't see a simple way to turn "Where you are going?" into anything normal - closest I can see would be "I don't know where you are going?" but that is quite a substantial change.
"Where are you going?" is fairly low-level - I can't see an easy way to explain it better.