Nice to have you in the Community space, @chelseamitchell1
I appreciate you for sharing the details with me. Rest assured I’m here to help and ensure you’ll be able to upload your CSV file into your QuickBooks Online (QBO) account.
In QBO, you can only upload CSV in either a 3-column or 4-column format. I’ve attached a screenshot below for your visual reference.
A 3 column format has a Date, Description, and Amount column. 
While the 4 column format has a Date, Description, Credit, and Debit column.

To get around this issue, let’s ensure we use the correct format in uploading a CSV bank transaction to avoid any errors. For more details about this, you can refer to this article: Format CSV files in Excel to get bank transactions into QuickBooks.
Once everything is good, you can check out this article for guidance in importing your transactions effectively in QBO: Manually upload transactions into QuickBooks Online.
Let me know if you need further assistance in uploading your bank transactions in QBO. I’ll be around ready to work with you again. Stay safe and well.