Select Opt. > Send, to add a recipient. You can enter a phone number or add a recipient by selecting Search to open Contacts.
You can find different options for writing a message, in Options when you are in the message field. You can, for example, insert symbols, and save or discard messages.
You can also turn on the predictive text (dictionary) from Options.
When you have received messages in your phone, open a message and select Options.
Scroll to Use number, and select Opt. > Call to call the sender. You can delete conversations, and add the sender to a screened list.