how do i file my sons taxes under my login? i dont see any option

[xmasbaby0]

When you use online TurboTax software you get one return per fee.

Each return needs its own email, account and user ID.   If you use the same account and user ID for a second return, the second one overwrites the first return and it is lost forever.  

https://ttlc.intuit.com/community/using-turbotax/help/how-do-i-start-another-return-in-turbotax-onli...

https://turbotax.intuit.com/personal-taxes/online/file-your-own-taxes/

[DoninGA]

You will have to create a new account since the TurboTax online editions can only be used for one tax return per account and User ID.

To create a new account will need to also create a new User ID and use a new email address.

Go to this TurboTax website and click on Sign up to create a new account - https://turbotax.intuit.com/personal-taxes/online/file-your-own-taxes/