We're unable to import Sales Receipts in QuickBooks Online, kristydetitta.
For now, you can only import bank transactions, customers, vendors, chart of accounts, products and services, and invoices using an Excel or a CSV file. More details about importing data are discussed here: Common questions about importing data to QuickBooks Online.
Although, you can manually record each Sales Receipt in your account. Just follow the steps in this article on how to do that: Create and send a sales receipt.
You can also look for an accredited third-party apps that offers importing of Sales Receipts in QuicBooks Online. Just go to the Apps menu and proceed to the Find Apps tab.
I'll be around if you have other questions.