facetime

I need an iPad so that I can take music lessons. The only thing I need the iPad for is Facetime. Since this is the only use, I don't want a new fancy iPad. I have found a lot of refurbished iPads, but my question is, if the iPad is no longer supported, does that mean I will not be able to use Facetime on it? Does Facetime have updates that would not be supported? For example, if I bought an iPad 2, would it work for me or not?

Thanks in advance for any help since I am a complete newcomer to the Apple world.