I'm here to help delete an invoice in QuickBooks Desktop for Mac, LouiseKS.

You can press the Command + D on your keyboard. Or go to the Edit menu while opening the invoice, then select Delete.

If you're using QuickBooks Online on a Mac PC, here's how to delete a transaction:

1. Find the transactions you want to delete, and open them one at a time.
2. At the bottom of the page, click More.
3. Choose Delete.
4. Click Yes to confirm the deletion.
   
   

You can also read this article for more information: Void or Delete an Invoice or Other Transactions.

I'm adding these links you can browse to help navigate QuickBooks for Mac:

• Keyboard shortcuts in QuickBooks Desktop
• QuickBooks Desktop for Mac 2020 User's Guide.
  
  

Stay in touch with me if there's anything else I can help you with deleting an invoice. I'm always glad to help.