Add bank account

Welcome to Community, @Lilian21.

I'll share the steps on how you can import bank transactions manually into QuickBooks. All you have to do is download a CSV file from your bank. Let me guide you how.

1. Sign in to your bank or credit card's website.
2. Follow your bank's instructions for how to download CSV files of your transactions to your computer. 
3. Check the date range for the download. Then, save the file on your computer's desktop.

After downloading, upload your file following the steps below.

1. Go to the Banking menu. Then, select the Banking tab.
2. Choose Upload from file or tick the drop-down arrow beside the Link account to see it.
3. Tap Browse and locate the downloaded file.
4. Follow the onscreen steps that'll guide you through the rest.
5. When you're ready, click Let's go.

Refer to this article for details: Manually upload transactions into QuickBooks Online.

Additionally, here's a link that covers all the tasks you can do when using the banking feature. It has topics with articles that'll help you along the way.

Keep me posted if you have follow-up questions or concerns with bank transactions. I'll be here for you. Take care and have a great day ahead.