Prevent other users to get Whatsapp notification Is there is any way to prevent other users to get notification when I joined Whatsapp?

Apparently, I don't want others to announce I'm using it as I'm trying to join it for only selective friends and family members.
Users don't get a notification or the like, when you join WhatsApp. (Maybe you're mixing up with telegram where users do get notified?)

But, when someone who has your number will try to send you a WhatsApp message, they will see that you have WhatsApp.

To prevent them from seeing that you have WhatsApp, you'll have to either block their number in WhatsApp or open a WhatsApp account with a new number that no one knows.