All Jews, both men and women, must fulfill the commandment to remember what Amaleik did to the Israelites. The paragraph about that episode, called Parashat Zachor (found in Parashat Ki Teitzei:  Deuteronomy/Devarim 25:17-19) is read on the Shabbat morning before Purim as a law established by Chazal (takana). The commandment is fulfilled whenever that episode in the Torah is read, even privately and at home, but there is special value in hearing it read in a synagogue on that Shabbat preceding Purim.