How to see learned words in the iPhone 6?

You know how it doesn't accept words that aren't real and you save it or whatever? How can I see those words?

You can't, unfortunately. If you have saved words you want to delete your only option is wiping the entire dictionary base and starting fresh under 'settings->general->reset->reset keyboard dictionary'. If you want to specifically add things, it's under 'settings->general->keyboard->text replacement'.