Starting with Windows 10, version 1809, the Windows Preinstallation Environment (PE) is released separately from the Assessment and Deployment Kit (ADK).
Refer to : Microsoft docs
To add Windows PE to your ADK installation follow the following steps:
1) Download the following installers from the Microsoft docs:
2) Install the Windows ADK for Windows 101809.
3) Run the Windows PE add-on for the ADK installer.
The WinPE files are installed at same location as they were in previous ADK installs.