“My Notes” is your personal chat. It is for your own record and can only be seen by you. You can forward/ share text, photos, videos, links, files, locations, contacts to “My Notes”.

To open “My Notes”
Go to the chats list page > tap more icon on top right hand corner (iPhone) or “+” icon on lower right hand corner (Android) > “My Notes”

You can star any messages in “My Notes”. See how to star a message.

Deleting items from “My Notes”
It is the same as deleting messages from chats, but “Delete messages for everyone” is not available.
See how to delete a message (iOS).
See how to delete a message (Android).

Note:
You cannot rename or change the profile picture of “My Notes”. If you have deleted “My Notes” from the chats list, you can reopen it again.