I am a complete beginner with Unreal Engine 4. Can I get some a good crash course that teaches everything I need?
You need to break things down into what you want to learn and look for information about those specific elements
It really depends on what you need 
UE4 (and game dev in general) is massive, and there are a lot of things going on. Some people settle with “just” learning to code, others to make effects. And so on.
So not sure if there is a crash course that will teach you everything.
But YouTube is your friend, and there are lots of great tutorials out there. I’d suggest following a tutorial series that shows how to make a game from scratch. Usually those give some insight into all the different areas.
Take a look at this for example, and pick a playlist that sounds interesting (maybe the “Mech Combat Game”)
Good luck on your journey!