There are two main ways to get this specific version:
The safest Creality Slicer 1.2.3 link download is always via creality.com/pages/download . Avoid random forums. creality slicer 12 3 link download
If you were told to find "12.3" specifically, it may be a typo for a different version of a fork (like Cura 5.x). Check your printer's manual for the specific recommended version. There are two main ways to get this
Why would you use version 1.2.3 instead of the new Creality Print? Here are its standout features: creality slicer 12 3 link download