You are welcome!
All “GameObjects” in Unreal Engine are of type Object that originate from UObject. Prefabs are blueprints of type Actor, so the empty GameObjects can be made as a blueprint of type Actor. Each blueprint can have components, just like Unity. So you can have a mesh with its logic as a blueprint of type Actor and place it in the world or Spawn it from another blueprint. You can have child Actors that inherit from a base parent class if you want too.
I am not sure if coroutines as it is in Unity exist in Unreal Engine, but there are Delay nodes in Blueprints that can pause the execution for a time – also check SetTimerByEvent. There are also a lot of flow control nodes that will do exactly what you want.
The logic layout will be different, but like I said, “the correct” way of handling stuff. Game Instance is the persistent script that runs when the game starts until its shutdown, the singleton equivalent in Unity. Almost all of the things that you manually do in Unity is already laid out for you in Unreal Engine.
Lastly, Unreal Engine is open source! So you can build it however you like. There are so many things, I can sit here and make a wall of text telling you how amazing UE is.
Try it out, it is free! But have a spare ~80 GB disk space