Click the green flag to move the mouse to centre stage. Use the keyboard arrow keys (Up, Down, Right and Left) to move the apple around the stage. Click the blue 'See inside' link to see the code on the apple.
If you are using an iPad or tablet, you my have a problem in using a keyboard. There is an easy way to code arrow sprites to move the apple. https://scratch.mit.edu/projects/511748630 See the Talking Apple at https://scratch.mit.edu/projects/431030173