You can create a sales receipt to generate a donation receipt in QuickBooks Online (QBO), then send it to the donor. Here's how:
Sign in to your QuickBooks Online account.
Click the + New button, then select Sales receipt.
Select the donor from the drop-down and enter their email address.
Enter the donation details.
Click Save and send.
Just in case you want to learn how to record in-kind donations or track donated inventory in the future, you can read these articles for more guidance: