Hey Rajat_bansal,
We'd recommend reviewing the information in this article as it provides options for managing app permissions on your iPhone: Control access to information in apps on iPhone
"Review or change access to information in apps
The first time an app wants to use information from another app, you receive a request with an explanation. For example, a messaging app may request access to your contacts to find friends who are using the same app. After you grant or deny access, you can change access later.
- Go to Settings
> Privacy & Security. - Tap a category of information, such as Calendars, Reminders, or Motion & Fitness.
The list shows the apps that requested access. You can turn access on or off for any app on the list."
If you need further assistance, we'd recommend checking with WhatsApp support. You can find their support page here: Contact WhatsApp
Thanks!