Hello there, @abmouton-gmail-c.
To upload bank file/transactions, you can manually upload the bank transactions using the CSV file. This is a way to bring the bank data when your financial institution isn't yet supported by QuickBooks.
Please know that you'll have to download transactions from your bank by logging in to your bank's website. Then, follow the given instructions on how to download transactions and save the file on your desktop.
Once done, upload them to your book by following these steps:
- Sign to your QBOA account and select Banking on the left panel.
- Click Upload transactions or Link account drop-down arrow and select Upload from file.
- Then, click the file you've saved on your computer.

Too keep your transactions organised and accurate, use these articles for guides:
Please visit again if you have more concerns. I'll be right here to assist you anytime. Take care and have a good one, abmouton-gmail-c.