If you mean your own artwork, then you'd take a picture of it, upload it to your computer (make sure you know where you're saving it), then select Insert > Picture in Word, browse in the location where you saved the photo, click the picture, and insert. If you mean an image from the internet or something, you can just save it to your computer and basically follow the rest of the steps above.
It’s not hard to find images to use online – just use an image search. This works well, but it’s worth noting that doing so isn’t necessarily legal. Most of the images you can find this way are owned by their original creators. This likely doesn’t matter if you’re only using something for private use, or even a school assignment, but if you intend to publish a work you need to make sure all rights are cleared.
Clipart is used to create a web-design, you can also draw up bills, posters, make cards, collages and wallpapers. Thanks to ClipArt and its individual elements, the new image is created including all the elements; it looks like it’s a photomontage, a creation of new design. At the same time, it will be a big plus if ClipArt goes without a background, since you do not have to waste time removing it. What’s the format of this kind of image? These are wide known PNG and GIF formats; the images can be saved both with a background and without it. There are aslo scrapbook kits for creativity, which consist of png images; those are a set of elements and backgrounds.