How to stop my Macbook Air whatsapp calls from getting diverted onto my Iphone?

Hi suhani24,

Welcome the Apple Community.

Re: Is there a way to stop my Iphone from automatically connecting onto my laptop's whatsapp calls?

Wondering which Macbook Air Model (Year) you have,

How to: Identify your MacBook Air model – Apple Support

and

how WhatsApp calls to your Mac are set up. (cellular from phone, wi-fi )

Perhaps Apple Support's articles (links below) can help you troubleshoot:

Make and receive phone calls on Mac or iPad - Apple Support

Make and receive phone calls in FaceTime on Mac – Apple Support

If needed:

MacBook Air Support:

(ie: "Get Support" link or use the app.)

MacBook Air - Official Apple Support

All the best :-)