create or replace type my_table_info_function as object(
ORDER_ID VARCHAR2(40),
OPER_KEY NUMBER,
STEP_KEY NUMBER)

CREATE OR REPLACE TYPE MY_TYPE as table of my_table_info

create or replace function MY_FUNCTION(vi_col1     table.col1%type,
                                       vi_col2     table.col2%type,
                                       vi_col3     table.col3%type)
 return MY_TYPE as

 V_RESULTS MY_TYPE :=MY_TYPE();

 V_RESULTS.EXTEND;
 V_RESULTS(V_RESULTS.LAST):=MY_TYPE(vi_col1,vi_col2,vi_col3);

return V_RESULTS;

Now in your query, you can directly select column from type as below;

select col1,col2,col3 from my_table_info_function