The below query will give you monthly reports:
SELECT CONVERT( VARCHAR(7),Checktime,121)'Year-Month',
EMPID,
Name,
SUM(Emp_Contrii) Total_Emp_Contrii,
SUM(Comp_Contri) Total_Comp_Contri,
SUM(TOTAL) TOTAL
FROM CANTEEN
GROUP BY CONVERT( VARCHAR(7),Checktime,121), EMPID, Name