Thank you for reply. It solved my problem with your help.
Now I wonder if I create a blueprint actor as a spawn when I have built three items together, the BP_Final appears in the scene and in it I want a trigger box to trigger the buttons. Is there a good way to do it?
I need trigger box inside blueprint actor to trigger the buttons. I tried it but listen to can not find that trigger inside blueprint actor. It only finds what is in the project and not inside the blueprint actor.