If you are going to file as Married Filing Separately you will need two tax returns.
Using the TurboTax online editions you can only complete one tax return per account and User ID. If you want to start another tax return with the online editions you will need to create a new account with a new User ID.
Go to this website and click on Sign up in the upper right of the screen and create an new account - https://turbotax.intuit.com/
