To manually upload the transactions in QuickBooks, you can download a Web Connect file or CSV from your bank's website. Then, save the file where you can easily find it and then import the transactions by following these steps:
Log in to your QuickBooks Online account.
Go to Banking.
Select Upload transactions, and click the Browse button and choose the file.
Click Next, and select the bank account where you want the transactions to be posted from the QuickBooks Account drop-down. Note: If you don't have an account, you can select Add new or create the account in the Chart of Accounts page.
Select Next to map the columns. Make sure the columns from the Web Connect or CSV file matches the columns in QuickBooks.
Hit the Next button twice.
When you get a prompt that the transactions will be imported, click Yes.
Click Let us go!
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