From your description I assume that you can see the menu. Are you able to see previously taken photos (before the problem) in the LCD screen. Unfortunately, it appears that the impact has damaged the image sensor ("CCD" the light sensitive chip that produces the image). Some of the information at the link below does explain the problem. Canon
Canon repair, at the link below, is probably your best option. If repair is not practical Canon has been known to offer discounts on new and refurbished replacements.
https://www.usa.canon.com/internet/portal/us/home/support/service-repairPlease keep in mind that my diagnosis & solutions provided are directly dependent on the accuracy of your description of the problem. As with any "do it yourself" fixes, success is a "team effort", since I can't see or touch the camera, and relies on the customer's manual dexterity and ability to follow the instructions well.If you require additional information, please use the Reply to Expert Tab to contact me. Click the ratings only after our exchange is complete and you are satisfied.
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