Can we eat together with non-Muslims?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

There is no harm in eating with the non-believers from the same plate, as the Kafir is not impure in himself. His impurity lies in his heart and his wrong belief.
But lawfulness to dine with non-believers is restricted to Halal food without the accompaniment of anything forbidden like music or the mixing of men with women or wine being served on the dining table.
The evidence for lawfulness is the Hadith reported by Ahmad from Anas that "Jew invited the Prophet (Sallallahu Alaihi wa Sallam) to eat some barley bread … and the Prophet (Sallallahu Alaihi wa Sallam) accepted the invitation" .
Allah knows best.