Canon PIXMA MegaTank G5050

According to the Canon support website the printer should work with Big Sur, the printer is

AirPrint enabled so does not require any drivers.

https://www.canon.co.uk/support/consumer_products/products/fax__multifunctionals/inkjet/pixma_g_series/pixma-g5050.html?type=drivers&language=en&os=macos%2011%20(big%20sur)

Does the printer appear in System Preferences> Printers & Scanners if not add it.

https://www.canon.co.uk/support/consumer_products/apple_airprint_guide/

Have you asked Canon?

Have you asked your question on any Canon forums, the probability of getting somebody

who has the same printer and macOS Big Sur is greater than asking here.

The set up instructions I posted a link to earlier are very easy to follow, did you read them.

the first link I posted takes you to the Canon Support page for that printer,

You can click on the topics for Set Up or download the manual.