If Allah himself ask to terrorists to stop terrorize the people will they stop? because they often says "Allahu Akbar"(God is Great !)?

Yes. Although they don't become terrorists because Allah told them to either, they become terrorists because some highly charismatic wannabe leader sparked fear and hatred in them of "the others" whom they had never met, but the guy told them they are evil & out to get them.
Just like Trump has done to mobilize the MAGA zealots.

They probably look at it as a test and go out and waste 10 people ..lol ..