INSERT INTO master_table (`Group_No`, `Group_Name`,`Order_No`) VALUES (6,'Purchase Account','SELECT Order_no FROM acc_group_master where Group_No=1')
How can i insert data into Order_No column.
You have surrounded your subquery with quotes '..' wich make it becomes a string and been inserted as it is in your database, simply remove quotes and apply brackets instead
INSERT INTO master_table (`Group_No`, `Group_Name`,`Order_No`)
VALUES (6,'Purchase Account',(SELECT Order_no FROM acc_group_master where Group_No=1))