If you would like to add/remove the recurring giving text message from the giving process, you will simply need to activate/deactivate that feature in your account.
You can toggle the recurring giving prompt for each individual Cause in your account, giving you fine-grained control. You can find your Causes under My Account -> Causes. Then, choose the Edit link for the Cause you'd like to change the recurring giving status for, and:
uncheck the box next to Allow recurring donations to turn it off OR
check the box next to Allow recurring donations to enable recurring donations