This should do what you want;

$response = GetRandomUnique(0,4)
if($response = 0)
Sayezb(" hello")

Elseif($response = 1)
Sayezb("How are you")

Elseif($response = 2)
Sayezb("i hope you are having a good day")

Elseif($response = 3)
Sayezb("Hi")

endif

Also, there are activities in the learn section which can give you the basics. For example, i would recommend following this tutorial: https://synthiam.com/Tutorials/Lesson/64?courseId=6

Use the learn section to find tutorials. Here's a direct link to the tutorials: https://synthiam.com/Tutorials/Course/6

Lastly, there is a question mark on every control. If you press that question mark, it will bring you to help of that control. Since you wish to use the camera, i would suggest pressing the question mark on the camera control. There are a dozen tutorials for the camera control.

The tutorials will demonstrate a very simple place to enter a script when the camera detects an object. It's in the camera Config menu and it's called Tracking Start. You will find it in the Scripts tab of the Camera Config menu. Simply insert something like

SayEZB("Hello, i see your face")

and that code will execute every time the camera detects something. You will have to enable Face tracking type. Also, read the disclaimers in the camera's manual page to understand the tracking types. Face tracking returns many face positives in a visually noisy environment.

Awesome, thank you both! I looked thru the tutorials but wasn't sure I was getting the right info, and was sure someone might have already done something simular that could help