I self-study Youtube Tutorials and UnrealEngine Docs. UE is Large, Powerful and keeps evolving, thus, learning is continuous. Keep experimenting and testing, everyday for as much as you can. Take breaks, when you need too.
I come to UE with intention to build various Multiplayer Games, Game Assets, and Tools and sell them through my own company. My studies are driven by this goal. I specifically learned Multiplayer Blueprints and started developing multiplayer constructions systems.
I acquire most of my media content from FAB and have no shame in doing so. Lots of things you can do to preexisting assets to make them look different. AND I rather use subsystems that save me tons of time.