You can type estimates paid in the search box at the top of your return and click Find and it will give you a link to Jump To it.
OR
To enter Federal or State Estimated Taxes Paid, including a state estimated payment made in Jan 2016 for 2015 (or Jan 2017 for 2016) go to
Federal Taxes (or Personal for H&B/Self Employed version)
Deductions and Credits
Then scroll way down to Estimates and Other Taxes Paid
Estimated Taxes - click the Start or Update button
See this answer, it has screen shots
https://ttlc.intuit.com/questions/3896471-i-sent-in-three-3-forms-1040-es-for-a-total-of-966-in-2016...
