Excel Spreadsheet that calculates mortgage payments based off interest rate

I need someone to create a simple mortgage calculator from an excel spreadsheet. Please see attached. I need cell B X Cell E to get the result Cell F. Cell C minus cell D equals cell F. Needs to be a mortgage calculator amortized over 30 years. For example: every product is amortized over 30 years. So if the 5/1 ARM was 4% , purchase price of 800,000, downpayment of 200,000, the mortgage amount would be 600,000. The payment would be $2,864. The user need to be able to plug in their interest rate, purchase price, and downpayment. The excel spreadsheet should calculate mortgage amount and principle and interest.