how to delete print statements?

Select a few, and try printing them to a pdf printer. Choose one that doesn't require each pdf to be named/confirmed.

See also https://help.myob.com/wiki/display/ar/Removing+transactions+from+the+print+or+email+queue?searchfacet=support:help&searchterm=Clear%20invoice%20queue&_ga=2.53735466.361531853.1685247411-1313550747.1557035026#expand-Toremoveabatchoftransactionsfromtheprintqueue