docs.microsoft[.]com/en-us/windows-hardware/get-started/adk-install
docs.microsoft[.]com/en-us/windows-hardware/manufacture/desktop/winpe-intro
docs.microsoft[.]com/en-us/windows-hardware/manufacture/desktop/winpe-create-usb-bootable-drive
Windows PE (WinPE) for Windows 10 is a small operating system used to install, deploy, and repair Windows 10 for desktop editions (Home, Pro, Enterprise, and Education), Windows Server, and other Windows operating systems. From Windows PE, you can:Set up your hard drive before installing Windows.
Install Windows by using apps or scripts from a network or a local drive.
Capture and apply Windows images.
Modify the Windows operating system while it's not running.
Set up automatic recovery tools.
Recover data from unbootable devices.
Add your own custom shell or GUI to automate these kinds of tasks.
Basically, when you create a bootable USB stick in an app like AOMEI, Paragon, Macrium etc., it uses WinPE for the OS that you'll boot to using that USB stick. Unlike those custom USB sticks, plain WinPE doesn't include software, though you can customize it yourself. You can also sometimes add & run apps for things like file recovery -- it depends on the app. Using the Microsoft tools you can also create a WinPE USB stick using the default FAT32, and have a 2nd NTFS partition for whatever.
To get & use WinPE, you have to install the Windows ADK Deployment tools, which isn't bad, then install the preinstallation environment [WinPE Add-on], which is about 3GB. The actual set of files you'll add to a USB stick or ISO is roughly about 300MB. It's usually recommended to use the latest win10 ADK/WinPE, regardless whether the device you want to use it with runs win7, 8, or 10.