You may want to refine your question a bit along with pointing to a specific point in the video for someone to watch. I skimmed through parts of it, but at 30 minutes long most people are not going to watch the entirety.
I’m not sure that I even saw the type of specific effect you were wanting to make because of this. Mostly I just saw a explosion of fire. The images you provided as examples left me a little baffled as well.
I’m also not sure that there are specific tutorials out there for this particular instance, but I’ll give you some pointers to get started.
To use this with your character you’ll want to apply it with Blueprints so that your character can spawn it.
This part is easy enough to setup within your character bp once you’ve got the particle system done. Use the Spawn Emitter at Location node >Emmiter Template selection you can choose your particle system.
I hope this helps and let us know how it progresses!
The information I linked above is a good start to understanding how particles and blueprints work so that you can get something going. You can even look at the first person template example for how our “MyProjectile” and “MyCharacter” Blueprints to see how these are setup to interact together. I don’t believe you’ll find a tutorial out there giving you the exact effect you would like.
You’ll find that you get the best responses from other users when you have tried to get an effect but are having trouble getting it just right. Showing and explaining the stumbling points and what you’ve tried that worked and did not work will help the staff and the community give you more advice for this type of effect.