To send SMS, go to Messaging > Send SMS. Here you can see two tabs present at top right corner in the send SMS page for sending sms to a Group or  Individual.

Send SMS to Group-

To send SMS to Group (Patient, Doctor, Admin etc), click on the Group tab present at top right corner of the page then enter the details that is message Title, Template ID (here Template ID is your DLT template registration ID which is used only in Indian SMS gateway), Send Through (SMS or Mobile App or both), Message and select Message To (Patient, Doctor, Admin etc) and then click on Send button.

Send SMS to Individual-

To send SMS individual, click on the Individual tab present at top right corner of the page then enter the details message Title, Send Through (SMS or Mobile App or both), Template ID (here Template ID is your DLT template registration ID which is used only in Indian SMS gateway), Message, Select user type from drop down and then search for the user name in the textbox then select searched user or users and click on Send button.