Yes, you will check that worked outside the USA (unless actually paid by the US government). Income is sourced to where the work is performed so if you worked in Germany, then the income will be German-sourced.
Depending on your particular situation, you may be able to claim a foreign earned income exclusion. The tests, the exclusions, and the deduction are explained in Foreign Earned Income Exclusion.
TurboTax
will guide you on taking the foreign earned income exclusion and foreign
housing deduction under Federal Taxes> Wages and Income>I'll choose what
I work on (or jump to full list)> Less Common Income (show more)> Foreign
Earned Income and Exclusion.