To restore WhatsApp backup from Google Drive to an iPhone, follow these steps:
Step 1: Ensure that you've backed up your WhatsApp chats to Google Drive from your Android device.
Step 2: On your iPhone, install WhatsApp and verify your phone number.
Step 3: WhatsApp will detect the Google Drive backup and ask if you want to restore it. Tap "Restore Chat History."
Step 4: Wait for the restoration process to complete, and your chat history from Google Drive will be transferred to your iPhone.