Income tax filling

Dear sir,

I have one question on consultancy bookkeeping For eg. Person dealing in Auto Consultancy. They dealing 100 clients in the year, like 30000x100= 3000000/-.and government fees and dealers payment is 29000x100= 2900000/- so overall margin income in this business is 100000/- in this situation how to calculate income tax? (note 3000000 cash deposits in bank and same withdraw in cash).

Note : in GSt showed 100000 is the income and paid gst.

Please any one provide a solution.