Hello, my Intuit account saved all my previous years' returns online, which are not useful for me. Is it possible to delete from my account? Thanks.

Prior year online tax return and accounts cannot be deleted.  TurboTax will maintain the past seven years of online tax returns, the same retention period as a the IRS uses for federal tax return.

Did you use the Online version?  Sorry No you can not delete accounts.  

Intuit - How to delete my account

How do I delete my account? | IRS Free File Program delivered by TurboTax