You appear to have multiple issues that are not directly related to one another. Let’s start with that display. That is the “Level” display. It tells when the camera is level to the horizon. Press the [INFO] a few times to cycle through all of the information displays. One of the cycles turns it off.
You also seem to be having issues with your memory card when you try to play back images in the camera. Make sure that you are only using full size memory cards, not the micro-SD cards that need the plastic adapter. Try to avoid the really high capacity memory cards. A capacity of 64GB is more than enough for photos. Only buy memory cards made major brands from reputable vendors. Amazon is not always a good place to shop for memory cards and camera accessories. Finally, always be sure to format the memory card in the camera prior to first use.
Lastly, you seem to have another set of issues with your USB connection to your PC. Make sure you have the latest copy of the EOS Utility 3 installed. Make sure your USB cable is a data cable, not a USB power/charging cable. If Windows asks you what to do when it detects your camera, tell it to “Take No Action”.
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