CR-10S / Ender5+ LCD Touchscreen Firmware Editing
I've been digging into the sources and from what I understand, it is not very easy to change the menus, you should possess some programming skills to change it. It appears that the screen is operating on its own firmware and the board is running a special fork from Marlin.

The screen is identified in code by constant CREALITY_DWIN. It appears that the screen receives/uses precreated images (from this download you find these screen captures). The code references the bitmaps by a number and a base number (ExchangePageBase). E.g. codeline:

RTS_SndData(ExchangePageBase + 78, ExchangepageAddr);


sends this image:



The specific code is found in this specific fork of Marlin in files Creality_DWIN.cpp and Creality_DWIN.h.

In order to make your own menu item, you need to add code to send new bitmaps and retrieve the touched position.