en_tn/gen/43/32.md

The servants served Joseph by himself and the brothers by themselves. The Egyptians there ate with him by themselves

This means that Joseph, the brothers, and the other Egyptians are eating in three different places within the same room. Alternate translation: "The servants served Joseph by himself and the brothers by themselves and the Egyptians, who were eating with him, by themselves"

The Egyptians there ate with him by themselves

These are probably other Egyptian officials who ate with Joseph, but they still sat separately from him and the Hebrew brothers.

because the Egyptians could not eat bread with the Hebrews, for that is detestable to the Egyptians

This can be translated as a new sentence: "They did this because the Egyptians thought it was shameful to eat with the Hebrews"

could not eat bread

Here "bread" stands for food in general. (See: rc://en/ta/man/jit/figs-synecdoche)