A Python embeddable package can install pip separately (pip with embedded python), but can it also install IDLE separately? As the embeddable package has pythonw.exe already, I tried to externally load idle.pyw with it, but more seem to be needed.
The IDLE IDE is part of the CPython standard library. It is usually an option packaged with tkinter, _tkinter, and, on Windows and Mac, an appropriate version of tcl/tk. Unless embedded Python comes with tkinter and _tkinter and tcl/tk is available, installing IDLE would be useless as well as difficult. It is not available as a separate package on pypi.org. (There are a couple of packages, such as https://pypi.org/project/friendly-idle/ that wrap or extend already installed IDLE.)
https://pypi.org/project/idle/ is a useless, non-functional, pretend package. "This is a program written in tkinter which acts as text editor.This can be used to edit file and as alternative of notepad." is a complete fiction. py -m pip install idle installs a 26-line idle.py. As reported in a comment, it tries to import a fictional module 'layout'. It later tries to run a fictional 'gui.mainloop()'.