I’ve felt the same pain. I’ve developed and developed in several other environments and engines, but I’m new to Unreal. The first few weeks of learning how the engine “ticks” are really painful, because I’m a n00b again, stubbing my toe on all the dumb starter things. I’ve gone through this with a large number of engines at this point, though, so at least I know to expect it 
Or you can just modify the controller / gamemode you’re already using to add the appropriate mouse behavior.
Also, if you’re trying to do something for the first time – try looking in the forums / AnswerHub / samples before you start doing your own development. It may actually save time, until you get to the point that you already know how to do it!
Btw: My quick test for whether a game engine is even worth looking at: Export an animated, skinned character out of 3ds Max, and see it imported, rendered, and animated in the engine, without having to utter any swear words. Many engines (some quite well known) fail this test…