Will using iMessage cost me money under my provider new charge?

My phone provider(telus) is adding a 40 cent per text to people outside of Canada so my question is, since me and my friend both have iPhones, if iMessage counts as a text or not cause it uses Wi-Fi?

No it won't

IMessage uses internet so you would need Wi-Fi or data. Also iMessage is a free service provided by apple therefore it doesn't use text messages so it would not count as text.