There is two ways to speak "I am a student."
First, if you wanna speak the elder or the unknown pepole, you can say "저는 학생입니다." "ju-neun hak-saeng ib-ni-da.
Second, if you wanna speak the younger or the same age people, you can say "나는 학생이야." "na-neun hak-saeng-i-ya."