Deductions & credits

To file a separate return for your dependent you need to set up a new account.  Online is only good for one return per account.  You can use the same email address for 5 accounts.

Https://ttlc.intuit.com/questions/1894512-how-do-i-start-another-return-in-turbotax-online 

 

Be sure on their return they check the box that says they can be claimed on someone else’s return.  And depending on their age and how much income they have and if they are a full time student you might not be able to claim them as a dependent.