Go to this TurboTax website to e-file an extension request - https://turbotax.intuit.com/irs-tax-extensions/
To file form 4868 Application for Automatic Extension of Time:
so the answer given here allows you to print out an extension and mail it physically. it does not allow you to electronically send the extension. i don't think turbo tax has that feature.
@tazngigi For future reference - You can get an automatic extension from the IRS if you make an extension payment on the IRS website for Direct Pay on or before the due date of the federal tax return - https://directpay.irs.gov/directpay/payment?execution=e1s1