Is "Kamu berapa umur?" different from above?

Yes.
"Berapa umur kamu?" literally means word-for-word
"How much your age"

umur = age
kamu = you

These two words "umur kamu" can not be separated.
They are the subject of the sentence.
They can also be shortened to "umurmu".

Berapa umur kamu?
Berapa umurmu?
Umur kamu berapa?
Umurmu berapa?

It's all the same.