Printing and Scanning under Big Sur with Canon MG7520

The MG7520 is supported as a networked device using Apple's built-in AirPrint driver. You won't need Canon driver support. Once you re-add that MG7520 with AirPrint, the System Preferences > Printers & Scanners panel should offer a Scan section where you can use Apple's Image Capture application for that scan functionality with this device.

If Canon has not provided a Big Sur compatible version of Image Garden, you will be dependent upon Image Capture, or optionally, the paid VueScan Professional application that supports the Scanner component without any Canon drivers or software necessary.

Once you enable AirPrint by re-adding the device in the Printers & Scanners panel, there should be a Scan configuration setting. Then you should be able to see the device when launching Image Capture. I doubt that you can initiate a scan directly from the device controls, but then again, I don't have a current Canon scanner here.

Big Sur was released in November 2020. Any drivers or applications posted by Canon prior to that date were never tested with the released version of Big Sur, and are suspects for compatibility issues. Try AirPrint and Image Capture with your MG7520.

Anything for this MG7520 after November 2020 may work. Else, just stick with the AirPrint/Image Capture path.

Use AirPrint and Image Capture where you are now.

Test it in Big Sur configured as I mentioned.