Yang Chen usually writes in German: Yang Chen (first name before surname).
On some occasions, such as when filling out a form, or even when signing an important signature, you will be required to write your surname first and then add a comma, that is, Chen and Yang.
Yang generally means ocean in Chinese names, while German Ocean means (das)Meer. As a surname, Chen can't be translated, so it is called Milchen. However, it is strongly recommended to use hanyu pinyin as the original name.
If you still don't understand, please ask.
Lucky year of the sheep!
-Sailing Goethe
PS: If the landlord asks this sentence, how to write it in German:
How is Chen Man Young's German?