You open a folder on the desktop by double‑clicking it with the left mouse button in the default Windows configuration.

Quick Scoop

On a typical Windows setup (Windows 10 or 11, unchanged mouse settings), a folder icon on the desktop opens when you:

  1. Move the mouse pointer over the folder icon on the desktop.
  2. Quickly double‑click the folder with the left mouse button (two fast clicks in the same spot).

This “double‑click to open” behavior is the default for desktop items like folders and shortcuts on Windows.

If you only single‑click the folder, it will just select/highlight it and not open.

TL;DR: Point at the folder on the desktop and double‑click it with the left mouse button to open it.

Information gathered from public forums or data available on the internet and portrayed here.