Although a person fulfills the mitzva of learning Torah in all parts of the Torah, his main focus should be on learning practical matters. The poskim stipulate that a person should learn practical halachas every day, and that by doing so he is promised a portion in the world to come. However, he should be meticulous about doing this every day, as stipulated in Tana DeVei Elyahu that if a person learns halacha every day he is promised a place in the next world. One should start first with Orach Chaim which is most prevalent and pertains to every moment of his life, and without proper knowledge of these halachas a Jew cannot function.