I want to make a meme from this image, so let's remove the text so we can replace it with what we want. In this video I perform a set of steps:
1. Use the polygon tool to select the area to remove
Demonstrating what not to do (skip these steps in real life):
2. Pick a color in the white space above the text
3. Press delete on the keyboard, filling with the foreground color
4. See that the result isn't what we want, so press Ctrl-Z to undo
Now to do it the right way:
5. Select Edit, Content-Aware Fill
6. Observe that the default option looks weird
7. Switch the Sampling Area Options to Custom
8. Reduce the brush size so it fits in the area of the poster with no text
9. Drag to draw green over the empty area of the poster
10. Observe that the preview looks good and Apply
That's it! Photoshop is magic.