Will you delete & deactivate my account. The real reason why I am deleting or deactivating my account is because I am no longer needed this account.

TurboTax accounts cannot be deleted.  You can simply abandon the account.  No one else has access.

Or are you referring to an Advantage membership that you want to cancel?

https://ttlc.intuit.com/community/downgrading/help/how-do-i-cancel-my-turbotax-advantage-subscription/00/25548