Does Unreal have something similar to this from Unity?

The first part of this tutorial series shows how to create the heirarchy of the body parts, which I get how to do in Unreal. This video shows how to set up custom animations within the Unity engine. Does Unreal have a way of doing this? Is it the Sequencer? And can I then use those sequences for my player animations in game?

Yes you can make custom animations, for example say you have a idle animation, and you want the character to go from idling to jumping, you should find a add key button at the top bar when your inside the animation, then you save that one as a new animation, I’ve seen people use sequence also.