How to make hole in wall in real time

That is one way to do it. The problem you will have to account for is the internal portion of an asset. The opacity does create a hole, however if a player turns sideways within the asset they’ll be able to see directly out of it due to hollow interiors, etc. Additional math will be needed to “cut” a hole and create a material that shows through the object, of which I unfortunately don’t have information on at present.