If you can't share or collaborate in the Notes app on your iPhone or iPad - Apple Support

To share or collaborate in the Notes app, everyone needs an Apple device with the latest operating system and enough storage. You can also use iCloud.com.

Why can't I collaborate on notes? - Apple Community

Get started with Screen Time on iPad - Apple Support

Can't share notes - Apple Community

Use iPad as a second display for your Mac - Apple Support

iPad User Guide - Apple Support

Share Freeform boards and collaborate on iPhone - Apple Support

Why don't I have the share button on note… - Apple Community

Can not open shared notes - Apple Community

Can't share notes - Apple Community

Draw or write in Notes on iPad - Apple Support

Sharing and collaborating on notes: a guide for Apple users

Share Freeform boards and collaborate on iPad - Apple Support