I have filed an easy extension but didn't pay the tax. Now I need to pay the estimated tax before tomorrow. Can you help me find that form?

[Cindy0H]

The form is 4868 which can be printed in TurboTax. Here is the form and instructions from the IRS:

https://www.irs.gov/pub/irs-pdf/f4868.pdf

[fanfare]

when you request an extension you're expected to pay the full balance.
go to www.irs.gov/payments and "Make a payment"
select Reason: Extension

Make a note of your payment  amount so you can claim credit for that when you file.