Deepika,
The it_data is a standard table, for example: it_data type standard table of, you can use the table type that you like. About attributes, declare as follows:
PARAMETERS:
p_ustyp TYPE usr02-ustyp OBLIGATORY.
DATA:
p_bname TYPE usr02-bname,
p_class TYPE usr02-class.
Remember, this is an example, but you can easily adjust with the previous code.
Regards,
Richard.