Epic Games' Samples and Projects
The combination of a sparse amount of documentation and a budding community can make it difficult to break into something as complex as Unreal Engine 4. You can glean some good gems in the form of snippets and assets from their content and project samples.
It's a little non-trivial to access, but you might find it worth doing.
Before proceeding, make sure that you have an Epic Games Account and have installed the Epic Games Launcher on your computer.
Browse the Learn tab
Open up the Epic Games Launcher and open up the "Learn" tab in the Unreal Engine menu. This brings you to all of the provided sample materials.
Clicking on one of the tiles, such as the "Vehicle Game" example game, will bring you to its launcher page which provides additional information. After confirming that you'd like to add this to your account, click the "Free" button.
Congrats! You should have access to that in the future.
Creating a Project Using Downloaded Content
You can create a project by visiting your library in the "Unreal Engine" tab and selecting the "Create Project" button associated with what you'd like to create a project of.
First Time Downloading That Content?
If this is your first time creating a project, then the launcher will need to download the assets first.
You can also create it from the product page where you initially added it to your Epic Games Account in the first place. You should be presented with the same dialog as the method shown above.
When presented with the project creation dialog, make sure to pay attention to the version of Unreal Engine 4 that you're creating the project for as well as the location of the project.
After the project is created, you can visit it at any time by visiting your launcher and selecting it from your list of projects. You can also open the UPROJECT file that is created inside of your project folder.