The last update that Canon released for the MP620 was for OS X 10.9. This driver will install and function fine on OS X 10.11 so here is a link to that driver.
With the errors you are currently getting it suggests you have a driver conflict so I recommend you remove the Canon printer files currently installed on your Mac before you install the driver I have linked to above.
First step is to open Printers & Scanners and remove the current model printer.
Then you need to open Finder and select Go > Go to Folder. Then copy the following line of text and paste it into the Go field and then press the Go button.
/Library/Printers/Canon/BJPrinter
This will show you the contents of the Canon BJPrinter folder. Select all the folders here and trash them.
Now restart your Mac and when you have logged back in, run the driver installer I have linked to above. When that has completed you can add the printer again via Printers & Scanners. Now see if you can print without the error.
Note that if the Canon driver does not work then there is an alternate driver package known as Gutenprint. With this package installed you can then add the printer using the Gutenprint Canon MP620 driver.