How to get emojis on the iPhone?

I have an iPhone & i download it emojis, but how can i use it on messages? Cuz it tells me i have to paste it if i want to send it. Its like if it was an app. I have the emojis but im not able to use it when im about to send a text message. What can i do?

Settings>General>Keyboard>Keyboards>Add new keyboards> emoji

My emojis gone so I need help finding them.