Youtube Playlist to get you started.
Besides that, it all comes down to math , physics and how much creative you can get. Not everything is done with pure geometry in games, many times stuff are faked with Shaders (Materials) and rendering techniques.
Blueprints is just visual programming. Anything in blueprints can be made on any programming language, thus, it comes down on adapting pseudocode or existing code of some language into blueprints (or interfacing from C++).
This is for more advanced people: Contributors