iPhone and Operating System
iPhone User Guide
About   *Settings > General > About
iPhone Storage   *Settings > General > iPhone Storage

Security
Passcode   *Settings > Face ID & Passcode
Apple Account   *Settings > Account Name
Recovery Contact   *Settings > Apple Account > Sign-In & Security
Legacy Contact   *Settings > Apple Account > Sign-In & Security

Apps and Layout
App Library   *Last Phone Screen
Widgets   *Touch, hold app icon, select Edit Home Screen, tap Edit
Move Apps   *Touch and hold app icon and select Edit Home Screen

Communications
Phone App   *Settings > Apps > Phone
Messages App   *Settings > Apps > Messages

Siri
Setup   *Settings > Apple Intelligence & Siri
Set Timer – Add item to Reminders

Settings – Accessibility 
Display & Text Size   *Settings > Display & Brightness
Display & Color   *Settings > Accessibility > Display & Text Size
Read & Speak *Settings > Accessibility > Read & Speak

Apple Account – iCloud
Storage *Settings > Apple Account > iCloud
Backup *Settings > Apple Account > iCloud > iCloud Backup
Syncing *Settings > Apple Account > iCloud > Saved to iCloud

Camera – Photos
Camera Controls – Live Photos
Capture Text – Live Text

Safari
Reader mode
Read text

Files App
Document Scanning

Notes App
Add media

Translate App
Camera Mode