Try using it on another computer to rule out a driver issue. If it double prints on another computer, you have a hardware issue. It would be nice to get a photo of the problem as well: Adding images to an existing question

If it’s just the driver acting up, you can fix it by removing and reinstalling the drivers. Make sure to use the ones online from Canon and not the CD, since the CD is never up to date when the printer is sold. If it’s a hardware issue, you’re going to spend more trying to fix it then it’s worth, so you’re better off getting a new printer.

It may be possible to fix it, but usually when you have an issue like this it’s generally serious and needs expensive parts to repair.

Also PS: Do yourself a favor and find yourself a nice HP or Brother mono laser printer, unless you genuinely need color. Inkjets only make sense if you print photos.