I have an older iPad. I think it is an iPad 2. how can I tell?

See the following: Identify your iPad model - Apple Support

See this support document for help. Identify your iPad model - Apple Support

Check at Settings - General - About - Model = ???

Enter those numbers in your favourite search engine, or post back here.

It's a iPad 2. You have a camera but no Siri or retina display.

go to Settings, General, About

scroll down to Model i.e mc770 then iPad 2

go to this site enter model number

http://www.everymac.com/ultimate-mac-lookup/