It is nothing special what I did and I didn’t achieve what I went for. I wanted a loading screen that would wait until everything in the level is loaded, which I don’t think any of the tutorials I watched did: Link 1 Link 2
I knew how to do that already, so I just made them, but I allowed the loading screen to appear at the start of a level. This would allow the game to build some of the level before loading. I chose a delay of 1s, because the levels were rather small.
I forgot how to disable movement, so I watched this to relearn the node: Disable input UE4
Summary
I am somewhat happy with the result, but I wished I figured out a better solution. I originally tried to make references of the objects and check them, but because they have duplicates it froze the game. This is the end result I had: