The Enemy don't spawn on the world

Do you have the red breakpoint? If not just do this after the SpawnActor:

if(EnemyBlueprint == nullptr)
     GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, TEXT("NULL Enemy Blueprint!"));

if(enemy == nullptr)
     GEngine->AddOnScreenDebugMessage(-1, 5.f, FColor::Red, TEXT("NULL Enemy Instance!"));