What is the best way to do an initial loading screen?

[AlexeyLM]

@Kris

Create your own game instance class and implement the Init event.
That will let you create the loading widget without waiting for a map to load.

To create an animated loading screen, add a throbber, hide it by setting its alpha to zero, then use Event Tick to cycle through the textures you wish to animate.
This is how I created the walking animation for the Ground Branch loading screen without making a new UMG widget in C++.

You can describe in more detail how you made the animation in the loop. And will it work on UE4 20? Thank.