Hi Ashish
You can claim all expenses incurred by you on your car as expenses including interest, depreciation, petrol, repair & maintenance expenses, insurance etc.
But it is advisable to you to deduct certain amount (usually around 15-20%)from these expenses as you are using the car for your personal purposes also.
As required by section 38(2), you have to deduct a fair proportionate amount towards personal expenses from the expenses incurred by you.
Now regarding claiming interest you have to collect Your car loan statement from the bank showing the interest paid on the car during the year.
Banks do not charge any amount for issuing such statements.
There is nothing which can prove that whether you are using the car for your personal puposes also but if you have the only car then it is assumed that you are also using it for your personal purpose.
Regards
Sumit Aggarwal
9971444888