I haven't received an invoice or download link

When you purchase a product you should immediately be sent a confirmation of your order email. This email contains information about your order and a link to download the product. (This is usually a PDF that takes you to Google Drive to download the product from there.)

Please check your spam/junk folders to see if the email has ended up in there.

If you have not received it, you can always see your orders and download your products from your account section.