is this your level blueprint? which other blueprint are you trying to execute nodes on from this one?
I dont think you can call the Beginplay event. Instead have the beginplay event call your own custom function and other blueprints can call that same function from a reference to that actor who has it.
Your main trouble seems to be - how do you get a reference to that actor so you can call that function? So thats ahy i ask which blueprint is trying to make which ither blueprint execute something