Missing 'Passwords' category in iPad Settings

Passwords saved in your keychain are no longer accessed from device settings. For iOS/iPadOS18, saved Passwords and account credentials are now accessed using the new Apple Passwords App; when you updated to iOS/iPadOS18, this new App will have been automatically installed on your device.

This support page may be of interest:

Use the Passwords app to create, manage, and share passwords and passkeys across Apple devices - Apple Support

The iPad User Guide is a rich (and often overlooked) source of information about your iPad and iPadOS. Here is direct link to the relevant section of the Guide:

View your passwords and related information on iPad - Apple Support

The Tips App, installed by default on all new models of iPad, provides a brief introduction - and leads you to the User Guide. In case you missed it, here is a link to the Tips App:

https://apps.apple.com/app/tips/id1069509450

In iOS 18, that setting has been replaced by the Passwords app. Look there for your saved passwords.

Use the Passwords app to create, manage, and share passwords and passkeys across Apple devices - Apple Support

Regards.