en_tn/num/33/03.md

General Information:

Moses lists the places the Israelites went after they left Egypt. (See: rc://en/ta/man/jit/translate-names)

during the first month, leaving on the fifteenth day of the first month

Here "first" is the ordinal number one and "fifteenth" is the ordinal number fifteen. This is the first month of the Hebrew calendar. The fifteenth day is near the beginning of April on Western calendars. (See: rc://en/ta/man/jit/translate-hebrewmonths and rc://en/ta/man/jit/translate-ordinal)

the people of Israel left openly, in the sight of all the Egyptians

"the Israelites left in plain view of the Egyptians"