Hello,
There’s tons of ways to do this.
But for simplicity-sake, I’ll give you one way.
You can create a Blueprint that contains a Box Collision. Add an ON_COMPONENT_BEGIN_OVERLAP.
From the overlap function, you can attach a function that spawns whatever you want into the project, using the SPAWN_ACTOR node.
Make sure that the translation is where you want it to spawn and not at the origin of the project (which it is, by default).
If any of these concepts are unfamiliar to you, just Google them, as they are basic functionality.