How do you print photos from iCloud?

Sign in with Apple ID and password from a web browser with account credentials at www.icloud.com in photos section elect photos , hold the shift key click on rest of photos to get selected ( select in few numbers ) and download them to Mac .

Add your printer https://support.apple.com/en-in/guide/mac-help/mh14004/11.0/mac/11.0

And follow https://support.apple.com/en-in/guide/mac-help/prtct002/mac

See - https://support.apple.com/guide/photos/order-professional-prints-pht6e15ea68/mac