History has shown when a more advanced society shows up to a lesser advanced society, the outcome is not good for the dummies. Aliens, if they should ever show up, would not have good intentions.
True, but as there is at least one non human highly advanced civilisation here with us, so far they haven't wiped us out. And it seems they, whever they are, have been here a very long time. On what we regard as "our" planet.
But I don't know where they originate. Extra terrestrial is one hypothesis. Ultraterrestrial or interdimensional are others.
But as professor Avi Loeb has often stated: visitors from outer space will show up one day. Could be tomorrow, could be 50 years from now. And we are not prepared.