set serveroutput on;

CREATE OR REPLACE PROCEDURE proc1
AS
    CURSOR cursor1 IS SELECT idStudenta, rok FROM STUDENT;
    v_stud cursor1%ROWTYPE;
    v_ocena Number(2,1);
BEGIN
    OPEN cursor1;
    LOOP
        FETCH cursor1 INTO v_stud;
        EXIT WHEN cursor1%NOTFOUND;
        SELECT wartosc INTO v_ocena FROM ocena WHERE idStudenta=v_stud.idStudenta;
        DBMS_OUTPUT.put_line(v_stud.rok || ', ' || v_ocena);
    END LOOP;
    CLOSE cursor1;
END;

EXEC proc1;