QuickBooks Online makes it easy delete an account and I'd be glad to show you how.
If you're referring to a bank account, you may need to disconnect the bank connection before deleting the account. Keep in mind that you can restore a deleted account, but may need to make corrections to journal entries and balances. If you're unsure, check with your accounting professional before deleting an account.
To disconnect an account:
In the navigation bar, click Banking, and then select the Banking sub-tab.
Select the account you want to delete, and then click its Edit icon, then Edit account info.
In the Account window, select Disconnect this account on save.
Click on SaveandClose.
The account stays in QuickBooks, but isn't automatically updated with downloaded transactions.
To delete an account: (Be sure you understand the effects if you fully delete an account.)
Click the Gear icon, and then click on Chart of Accounts.
Select the account you want to delete in the list.
Click on the drop-down arrow beside Viewregister and select Delete.
Confirm that you want to delete the account.
Give this a try and if you have questions, I recommend contacting our support team using this link.