Hi, @lalajee
Thank you for posting in Microsoft Q&A forum.
I did the same steps follow you, it copied the files to the new folder C:\WinPE correctly, the boot.wim file is under C:\WinPE\media\sources.
When Copype copies the Windows PE base image to the <WorkingDirectory>\Media\Sources folder, it renames the base image from Winpe.wim to Boot.wim.
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