why the phone scrreen locked during calls and can i stop that?

[AC Question]

In moto g 3rd with android 6 i cant find calls options (like:*Call*Barring - block incoming/outgoing*call;*Call*Forwarding - transfer all/selectedcalls*...*Moto G*(3rd Gen.)*... )and cant adjust
the time for screen lock, i want to be able to see call timer during the call and end call with touch icon Not with Button? is that possible??
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