Filing taxes for someone who died

NO, do not use your account!  Unless you are filing a Joint return with them.  

Online is only good for 1 account and 1 return. You can use the same email for 5 accounts and returns.

You can start another return in TurboTax Online by:
Logging out if you are in your account
Choose what TurboTax Online product you want to use for the second return
https://turbotax.intuit.com/personal-taxes/compare/online

Create your account screen
Set up a new login for the second return
Start working on the new return

Or use the Desktop program.  The Desktop program can do unlimited returns and efile 5 for free.  And you can use any Desktop version, they all have the same forms.  So you could use a lower version than you might need in the Online version.