Hi there h-kaur-wefx-ca,
It's vital that your customers receive the correct information about the services you offer. QuickBooks online is a great tool able to help you create and send forms for customers, such as invoices, estimates, and sales receipts. I can provide some information about emailing from QuickBooks Online.
QuickBooks Online only has the ability to email a form to a customer, such as an invoice, a credit memo, an estimate, or a statement. There isn't the ability to send a general email within QuickBooks Online without sending one of these forms, or a reminder of one of these transactions. I can see how being able to send general emails with attachments to customers would be a feature that you'd like to see in QuickBooks Online to help inform your customers. I recommend leaving feedback in the system by clicking on the Gear Icon, then Feedback. The comments made in that section are taken into consideration when designing new features for the software.
if you have any other questions, feel free to reach out here.
