Where do I enter IRS refunds I received from 2018 federal and state returns?

Federal tax refunds are not entered on a federal tax return.  Stimulus payments received are not entered on a tax return.

State tax refunds received in 2019 are entered on a federal tax return.

To enter a state or local tax refund (Form 1099-G) -

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to 1099-MISC and Other Common Income
• On State and Local Tax Refunds on Form 1099-G, click the start or update button

Or enter state refunds in the Search box located in the upper right of the program screen. Click on Jump to state refunds

be careful in entering state refunds. in some cases they are not taxable.  here are some reasons: 

you did not itemize for the year of the refund

you paid alternative minimum tax (still may be partially taxable)

you itemized but took the sales tax deduction.

the state refund exceeds the sales tax deduction you would have been allowed - only the excess is taxable

TT usually handles this correctly if you used TT in the prior year.

the exceptions are for refunds for earlier years - like a 2017 refund in 2019 and if you are in AMT for the year of the refund.