my samsung galaxy s5 glass broken ,

[AC Question]

now the screen goes on but touch screen doen't react. what can be the reason or how i can solve the problemor which part i have to change

 

[Rukbat]

now the screen goes on but touch screen doen't react. what can be the reason

The touch screen is part of the glass.

or how i can solve the problemor which part i have to change

You don't change any part. Changing the glass uses a heat gun. Too much heat and you destroy the whole screen. Too little and the glass breaks into shards and punctures the screen under it, ruining the whole screen. It usually takes 5 or 6 screens before you get a feel for it. (Which is why repair shops keep phones that are so far gone it doesn't pay to repair. They're like cadavers in medical school. You can't kill a corpse by making a mistake.)

You bring it to a repair shop and pay them to replace the glass and digitizer (the touchscreen).