When you link a bank to account to QuickBooks the user is able to track financial transactions, income, and expenditures, profits, and losses in the business.
1. Open QuickBooks application and choose the gear located on the top of the home screen
2. Select Chart Of Accounts and click on the bank you want to connect in the action column
3. Next, click Account History and select Connect Bank from the drop-down list
4. Finally, with the on-screen prompts Finish the bank connecting process

I hope the steps finally help you to link a bank account to QuickBooks.