How do you undo on a US keyboard mac set to German keyboard, and where the ^ symbol from said keyboard as well?

Question

I have originally a US keyboard so the degrees/up arrow sign on the top left of an ORIGINAL GERMAN KEBOARD is actually the <> keys for me.

When I do Ctrl+Y it doesn't undo, nor does ctrl+z.

Answer 1

Macs don't use Ctrl Ctrl ⌃ as the main modifier, they use Cmd Cmd ⌘

Undo should still be Cmd ⌘ Z on a German Keyboard, between T & U.
Not all apps use Cmd ⌘ Y for Undo, Many use Cmd ⌘ Shift ⇧ Z instead. Adobe apps are switchable in prefs.

For any other app, you'd have to let us know which it is. Upload a photo of the actual keyboard & a snapshot of the layout from system prefs, eg