Newbie VLOOKUP question

I am building a credit work sheet, that will have columns as such,
Product | Amount | Rate | Term (yrs) | Payment (Monthly) | Cost per Year*

The product being already set up on a drop down menus to choose financing products such as a mortgage, credit card, etc...

I want to be able to auto fill my payment column with forumlas associated with the product type. How do I do this? I think it is a vlookup statement but unsure of how to set that up properly in this current situation.

I have attached my current worksheet.

Thanks for your help,

Credit Worksheet.xlsx