en_tn/exo/12/02.md

For you, this month will be the start of months, the first month of the year to you

These two phrases mean basically the same thing and emphasize that the month in which the events of this chapter take place will be the beginning of their calendar year. (See: rc://en/ta/man/jit/figs-parallelism)

the first month of the year

The first month of the Hebrew calendar includes the last part of March and the first part of April on Western calendars. It marks when Yahweh rescued the Israelites from the Egyptians. (See: rc://en/ta/man/jit/translate-hebrewmonths and rc://en/ta/man/jit/translate-ordinal)