Does Apple charge for iMessage with no service?

I don't have service (AT&T, Verizon, etc.). I don't pay monthly for service. Does that mean I can't call or text someone without getting charged? I just got mine, I don't know much about iPhones. Sorry. But please help.

Added (1). I'm confused on how it works. Does it let you text free with just Wi-Fi or do you need a plan AND Wi-Fi?

It uses internet, Wi-Fi if you got it but no service means no free internet via simcard then use Wi-Fi for its free to use because it uses internet to message only someone else worldwide who too is using imessage, like whatsapp but apples own version

No. Imessage works with Wi-Fi. It's a free system the Apple offers.