InfoPath Dev

I am trying to have the user select an option button and then based on that selection a few of the following fields will become required fields. How can I accomplish this?

you will need to accomplish this thru the use of rules and validation. If you create a sister field for each of your conditionally required fields you can check the value of the sister. even if the value is 1 or 0, check the box set value to 1,  if the sister field =1 and field is blank, hide your submit/save button. Add formatting around the field. something like this should get your desired results.