Okay, no way to dance around this one. The official documentation for Unreal Engine isn’t all that useful. If it’s not just auto-generated from heaps of engine code, there is some really wrong. Rarely, if ever does the Unreal Documentation provide much help besides telling you which file to include in order to make a type compile. (And honestly, if you’re not getting that for free from Rider or Visual Studio, you need to upgrade.) If you have a question about the return type? Go dig through the function in the engine code. Wondering if you can safely put nullptr as an argument? Give it the old college try and see if it crashes.
All is not lost, however! There are a many great scholars out there compiling their knowledge onto their own sites to help us Information Peasants. Here are some useful sites for Unreal Engine beginners such as myself.
Ben UI
Ben has tons of helpful tutorials, videos, and reference materials. While he advertises as a UI guy, and there definitely are a more UI focuses tutorials on the site, Ben also has a lot of general purpose knowledge to impart. One of the strengths of this site is that there are a lot of articles which cover the plethora of ways to do something, noting the tradeoffs. (Or sometimes the reason why to never do it that way.)
There are many different types of pages from tutorials, discussions, and documentation. Here is an example of a great Documentation Page that I reference constantly: https://benui.ca/unreal/uproperty/
JIP.dev
https://jip.dev/notes/unreal-engine/
JIP, JORGE ISRAEL PEÑA, is a software engineer with a knowledge on a great many things. It seems part of his learning method is to extensively document. One of the many topics that he has transcribed his learnings is Unreal Engine. His “Notes” cover a wealth of topics from top-to-bottom, and could be used as beginner reading. Starts with project structure, naming conventions, and terminology and then moves through increasingly advanced topics such as Garbage Collection, Building, and more.
Unreal Slackers
A little disappointing that this is a Discord server and not a Slack. You know, just naming wise. However, this is a good community that has a lot of members. It can be kind of hard to follow in some channels, but it has a lot of knowledge. Sometimes it can be hit or miss with questions, but it’s a good place to try regardless.
The Unreal Developer Network
Okay, so this one is basically the official GOOD forums for Unreal. It isn’t free. But for every Unreal forum post you find on Google with the same few suggestions that aren’t relevant, the UDN has a depth of serious developers with in-depth answers.