When you file an extension, do you receive a confirmation from the IRS/TurboTax?

The IRS does not send any confirmation of an extension. They will only contact you if your extension is rejected.

If you e-file an extension with TurboTax Easy Extension you get an email from TurboTax when your extension has been accepted.

It's too late to file an extension for your 2023 tax return. The extension had to be filed by April 15, 2024. Just file your tax return as soon as you can. If you are getting a refund there is no penalty for filing late.

A Tax Account Transcript from the IRS (not a Tax Return Transcript) will show that an extension was filed. To get a Tax Account Transcript, go to Get your tax records and transcripts on the IRS web site.