how to text with a iphone 7

Open the Messages App, the green icon with the white speech bubble.

Tap on the new message icon enter a number to text to, and a message and tap on the send button.

See here for details: Use Messages on your iPhone, iPad, or iPod touch - Apple Support

What bells and whistles?

Just write the message and tap send. If you are getting the effects screen, you are holding down the send button. Don't hold down on the send button, just a quick tap is enough.