On estep calibration - it varies by printing temperature, and do it under load (normal printing conditions, as opposed to with the bowden tube removed) : r/ender3
estep calibration" 3D Models to Print - yeggi
E-Step Calibration of a 3D Printer Extruder - YouTube
3D Printer XYZ Step Calibration Tool (Customizable) by geit_de - Thingiverse