Drawing the curtains can mean closing them, especially at night or for privacy.
Example: As night falls and the lights are turned on in the house, I like to draw the curtains so that I don’t feel like I’m being watched by outsiders.
Drawing the curtains can also be done by pulling the curtains to let more in more light or to discover what is behind them.
Example: In the movie, The Wizard of Oz, Dorothy’s little dog Toto reveals who the Wizard really is by drawing the curtain.