I can see that you want to use the new updates for the estimate platform, LHC40.
Currentlty, our product experts are currently in the process of enhancing the new invoice layout continuing to roll out the new invoice experience to some customers, and getting feedback in QuickBooks. Thus, this rollout update will gradually change into your QuickBooks Online (QBO) account.
Rest assured that you’ll automatically be able to use the new experience once the update occurs, with no additional steps needed on your end. For more details about the new updates in the estimates layout in QBO, you can visit this article: See what's new with estimates and invoices in QBO.
Additionally, you can read this resource to personalize and add specific information to your sales forms: Customize invoices, estimates, and sales receipts in QuickBooks Online.
For future reference, here's an article you can visit to help you account for your customer's payments: Receive invoice payment.
You can tag me in your reply if you need more help managing your sales transactions and accounts in QBO. It's always my pleasure to back you up. Keep safe, and have a good one.