Ive already paid my state taxes and only need to file/pay federal. how do i separate the two?

When going through the filing steps, select "File by Mail" for the state. This will allow you to bypass the state e-file. For the state payment, you can select the option to mail a check to bypass the state payment screens. Of course, you don't have to mail the state return/pay if you already e-filed it and paid the balance due.

Not sure what you have done with state.  Did you mail in the state return?  But you still need to file the federal return?  Here's some options for paying the federal tax due.

How to pay a Federal Tax due
https://ttlc.intuit.com/community/tax-payments/help/how-can-i-pay-my-federal-taxes/00/26212

You can pay the IRS directly at
https://www.irs.gov/Payments

Or here is a blank payment voucher to send in with a check
https://www.irs.gov/pub/irs-pdf/f1040v.pdf