If you are a US citizen or permanent US resident (green card) you are require to report all of your worldwide income on a tax return each year.  Your foreign earned income is reported on a Form 2555.

To enter Foreign Earned Income -

• 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 Less Common Income
• On Foreign Earned Income and Exclusion, click on the start or update button

Or enter 2555, foreign income in the Search/Find box located in the upper right of the program screen.  Click on Jump to 2555, foreign income

Also see IRS Publication 54 Tax Guide for U.S. Citizens and Resident Aliens Abroad - https://www.irs.gov/pub/irs-pdf/p54.pdf