"他的爸爸是德国人。"

Translation: His dad is German.

[grippygecko]

And this relates to food ? Feels off topic to me?

[AbuDhabi6]

I think Duolingo randomly gives you some previously learned material mixed in with the new, so you don't forget.

[o0oo0o]

"His father is from Germany" should be accepted since the previous section regarding nationalities all translated "xx人" as "from xx country"

[Celticfiddleguy]

That's probably more of a "technical" mistake on Duo's part. You can see the difference in an example: a fictitious Wang Pengli is from China (来自中国 or 从中国来) so ethnically he's Chinese (中国人) but he's become a naturalized US citizen so he's also an American (美国人)