A beginers of beginner's guide?

You are right stuff like UCLASS() and so forth are macros for UE 4.
You dont have to know what happens under the hood you just need to know how and way to use them.
See Gameplay Classes for more info.

When it comes to what a member is for look it up in the Unreal Engine API Reference.
Start small and you be a pro in “no time” :slight_smile:

https://wiki.unrealengine.com/Entry_Level_Guide_to_UE4_C%2B%2B

Good Luck.