Can I file a federal extension can that be done online?

Yes you can.  Use this link >> There is no fee to file an extension.   File an extension by April 15, 2024, and have until October 15, 2024, to finish your taxes.   It is an extension to file - not an extension to pay your taxes; the bill is still due by 04/15/24 even if you file the extension.   

Avoid penalties and get a little extra time to file your return - Learn more about penalties

Yes absolutely.  You can do that from the TurboTax website: https://turbotax.intuit.com/irs-tax-extensions/

Sounds like you're busy!  Having said that, it's best to file now using what you know as long as you don't have to pay a much or hopefully get a refund, then you can re-file a corrected return later this year when you have more time to do your taxes.