Hey Giantbird,
It sounds like you're having an issue with AirPrint with your Canon printer. We can understand wanting to get that resolved so you can get back to printing on your Mac. We want to help.
First, we'd recommend trying these steps in the following article: Print wirelessly from your Mac to an AirPrint printer
- Make sure that you have the latest version of macOS. Choose Apple menu > System Preferences, click Software Update, then install any software updates listed.
- Try connecting the AirPrint printer to your Wi-Fi network using a direct connection or through bridging. The printer may then be able join the Wi-Fi network and work wirelessly.
- After turning on your printer, wait a few moments before trying to print. Some printers might take a minute or two after powering up before joining the network.
- Be sure to connect your AirPrint printer directly to your Wi-Fi network or the Ethernet LAN port on your AirPort Base Station or AirPort Time Capsule. You can’t use AirPrint to print to a printer that’s connected to the USB port of an AirPort Base Station.
- Check with your printer’s manufacturer to see if any updates are available for your printer model.
"
We'd also recommend checking for updates to your printer software: Update printer software on Mac
If you continue to have the issue, you may also want to try uninstalling and reinstalling the printer. This article explains how to remove a printer: Remove a printer on Mac
Thanks!