1.5. Clone stamp tool
The Clone stamp tool in Photoshop is useful for cloning areas of a picture. This might be to cover something over or duplicate it.
Copy the balloons picture, switch to Photoshop, create a new canvas and paste it.
Right click and copy this image to use it
Choose Clone Stamp from the toolbar on the left.
Once selected, you hold Alt (near the space bar) on the keyboard and choose your target area. This the area you want to use so in the above example, you would hold Alt and click on one of the balloons.
You then let go of Alt and move the mouse to a new area of the page. Left click and paint to clone your chosen area.
The best way to learn it to have a go and practise so you can see what happens but if you are stuck, this Clone stamp tool video might help.