Americans have different words to have the same meaning. These are called synonyms. Oftentimes, these evolve from slang. Americans often do say they are finished when a task is complete, as well.
You can say "Ua pau au" in Hawaiian to mean "I am done" or "I have finished."
"I am done" translates to "he terminado", as in "I have finished". In Spanish, we say "Ya termine" (I finished already)
done
To say "done" in Hawaii, you can use the word "pono," which means complete, finished, or good.
You can say "J'ai terminé" in French to mean "I am finished".
In this case, I believe you mean "we were finished (ended) a long time ago". That would be "Nos terminamos hace mucho tiempo".
Big mac
'The discussion is done' would technically be allowed, but can be better expressed with '... has been completed', '... is finished', '... is over', etc.
I think you mean Pau pronounced Pow. It means done. Pa'u Hana (pronounced "pow hana") is a Hawaiian phrase literally meaning, "finished work",
pau - it means done, finished
Finished. Done. Nothing further to say. Finalized. Out and over.
There are many dialects, but I am assuming you want a more Jewish dialect. This would be "Heya Khelal".