MY BUSINESS PURCHAED A CAR WHERE DO I ENTER

as you go through your business entries there should be a question about acquiring a vehicle. however, if there is no business use there is no reason to enter it.

If this is adding a vehicle for itemized deductions or energy credits, this will go in the Deductions and Credits section, from the menu bar on the left. Scroll down to Cars and Other Things You Own.  If it is not eligible for an energy credit and is not a business vehicle, you will not need to enter the purchase. 

If this is for a vehicle you use with your Self-employment, it will go in the Schedule C section, in Expenses, under Vehicle.