Yes you can, as long as you have a self-employment business and stay within the yearly limits established by the IRS for both types of contributions as established by the IRS here for Roth IRA contributions and here for the SEP Roth IRA contributions.
You can also refer to these FAQs from the IRS as it directly relates to SEP's.
Please also see where do I enter my traditional or Roth IRA contributions and where do I enter my SEP IRA contributions for more details on entering each of these contributions into TurboTax.
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