This will be the first thing you see once you open up twine and start creating your first narrative. Each white box is called a "passage". After you double click on the passage to edit, it will expand into a text box that you can work on. As an example, type the following text into the box:
You are facing two doors. One is a beautiful shade of blue that looks as if it is made out of water. The other is a dark and dingy door with a spider web clinging to the edge.
Just like in any other story, you as the author will get to decide what happens next. To provide options in Twine, you need to place square brackets around the words you want clickable within the game. You can also add a vertical bar to provide a name for the target passage to the right of that bar, as shown in the chart above.
Then you start a new paragraph and write the following directly below the text you already have in the box:
Do you want to open the [[the blue door?|Blue Door]]
Or do you want to open [[the black door?|Black Door]]
Once you click on the X in the upper-right corner of the box, you will see two new passages on the screen. By double-clicking on those, you can create what happens to the player once they select one of the doors. To try it out, exit out of the text box and hit the play button on the bottom right of your screen.
Good job! Now you know how to create a basic story in Twine.