Face ID & Passcode is usually located right under Siri & Search.
If a customer is not able to locate Face ID & Passcode in Settings you can guide them using these steps to enable.
Apple hasn't changed the location of this menu. Most of the time this happens by accident.
On iPhone, there is a setting called Screen Time, Screen time allows you to set limits for what you want to manage. In this case, you are going to navigate to Content & Privacy Reactions.
- Open Settings and tap on Screen Time ( typically located near top of settings )
- Scroll down to Content & Privacy Restrictions
- Scroll to the Allow Changes section and tap on Passcode Changes
- Select Allow
** Face ID & Passcode should now show up in the main settings menu
Link to website for reference: https://www.iphonetricks.org/face-id-and-passcode-missing-in-settings-fix/
**Attached are photos to use for reference