https://wccftech.com/you-can-now-lock-your-chrome-tabs-using-face-id-or-touch-id-on-iphone-and-ipad/

Good news! You can now lock down your Chrome tabs using Face ID or Touch ID on your iPhone and iPad. The feature is now rolling out to everyone with Chrome 92.

This feature is currently limited to Incognito tabs. Enabling this feature is actually quite simple. Go to your Chrome settings, then under Privacy enable the Lock Incognito tabs when you close Chrome feature. Whether you have Face ID or Touch ID, it will be required to gain access to your Incognito tabs.