This article explains how to sync your Gmail contacts with an existing Gmail account on iPhone, and how to sync your Gmail contacts when you first set up a new Gmail account on iPhone. Instructions apply to iPhones running iOS 14 or iOS 13.
How to Sync Gmail Contacts with iPhone
You can choose to sync your Gmail contacts when you first add the Gmail account to your iPhone, or you can add them to an existing Gmail account later.
Here's how to transfer Gmail contacts to your iPhone.
Open the Settings app on your iPhone.