Open the Notes app and type in a few lines of text. You must have more than one line of text. Type in a paragraph.
Then press in one of the middle lines of text so you can see the cursor.
Then press the footswitch. The cursor should move up and down between lines. If it doesn’t, then the pedal is not set to arrow up and down.
The pedal should do the same thing as when you use the up and down arrow keys.