I never touch this stuff in unreal engine 
so What is common workflow/feature that people use in unreal engine to create destruction in unrealengine?
in destruction here I mean like when we shoot or put a bomb at wall and boom!!! the wall is destroyed.
what is common feature/workflow people use for this?
are you talking about dynamic or pre-baked destructive stuff?
Unreal engine has built in destructible mesh tools. https://docs.unrealengine.com/latest/INT/Videos/PLZlv_N0_O1gYeJX3xX44yzOb7_kTS7FPM/-gGiEmYj4oE/
Start with those! 
I think I need both of them
wow, thanks
I hope we can make not only entire mesh is destroyed, but just little part of mesh (just for bullet hit a wall, so not entire wall will destroyed
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by the way, will it bring big impact to our game performance if all building like wall/window/door in the level is destroyable?
I want to try make shooter game, I really love when we can destroy the windows, door, wall, the building like common shooter game.