Is there anyway to replace the word invoice to statement when sending payment reminders

Yes, there's a way to change the Invoice to Statement, @Wildjeepgirl. Happy to outline the detailed steps to achieve your task. 

We can achieve your task by changing the invoice template prior to sending a payment reminder. With this, I'd recommend creating a new template or editing an old one.

Do the following:

1. Go to the Lists and select Templates. 
2. Press Ctrl + N, then choose Invoice and click OK. 
3. Hit the Additional Customization tab. 
4. Pick Header, then change the Default Title.
5. Select OK. 

Then, open the invoice you want to send and change the template. See the sample screenshots below for your reference:

For more information, visit this article: Use and customize form templates.

After that, you may now send it to your client. For further guidance, click this link: Create payment reminders for invoices and statements. 

For an additional guide, while modifying email templates when sending messages from QuickBooks, you can also open this link: Create custom email templates in QuickBooks Desktop.

Let me know if there's anything else I can help you with. I'm more than happy to help you anytime. Have a great day!