Loading and unloading stream level in order of completion

There are stream levels that I need to load and unload in order to array index what I arranged. So, a level should load after the previous level has been loaded or unloading should be done in the same way.
For example, three levels must be loaded in order and then the levels to be unloaded must be unloaded in order. I need to process multiple levels at once, sequentially.
I couldn’t find the way to use FLatentActionInfo properly. I tried OnLevelLoaded and OnLevelUnloaded with AddUniqueDynamic also.
In what way can I do this?