You can add a new account by clicking the New tab at the upper right corner in your Chart of Accounts. To delete an account, you can click the arrow next to View register and select Make account inactive.
You can also merge the old account to the new account to transfer the transactions easily. For additional information, please refer to this article: https://quickbooks.intuit.com/community/Income-and-expenses/How-to-merge-accounts-customers-and-vend...
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