In your flat, you have two primary options for opening the windows:

To open the windows in the standard manner, simply twist the handle in a clockwise/anticlockwise direction. This will allow the window to swing open fully.

For a tilted opening, which is useful for ventilation while maintaining security, twist the handle upward. This position allows the window to remain partially open at the top.

When you no longer need the windows open, simply close them by reversing the opening process. Ensure that the handle is turned back to its original position to secure the window properly.