If I buy an iphone 5 from t-mobile do I need to change a new data plan?

My boyfriend is planning to get me a iphone 5, but since I'm under my father's plan & my father refuses to get me an iphone. Can I get the iphone and just put my sim in- will it work the same? Or do I have to go to t-mobile myself and change it to another data plan?

No need to change the data plan. Enjoy!

As long as the iPhone is an iPhone Factory Unlock then you will be able to use your sim card in it. No need to change another data plan.