I am an unreal engine user and I make tutorials on unreal engine . You can check out my channel and learn from my videos . I teach in a simple and easy way so everyone can understand .Generally I am a 3D artist, but I also have some extra knowledge on game development in Unreal.I am going to share you both of my 3D art and game development experience which I learned through years .Be happy:)
Unreal engine is basically a game engine. But it also gives you the ability to create VFX, 3D animations, virtual productions, CGI, 3D environment etc. It's just like any other 3d softwares like blender and Maya. But It's different at the same time. I hope so you understand.
The acceleration of the Workflow is too pronounced, particularly during the procedural step of adding the folliage, we cannot see how you are doing it.
I belive those megascan bridge meshes require a lot of optimization and they are not game ready at all ? Last time I check they are 4-8k textures and lots of poly which cause eating all the fps.