To edit or delete a note, open the Notes Section for the case or contact that the note is linked to.
In the Notes Section, find the note you'd like to edit or delete, then click on the Arrow at the end of the note description.
The full details of the note will get exposed, along with some options. Two of these options are Edit Note or Delete Note.
Clicking on Edit Note will put the note into an editable state. You can update the subject, body, and date of the note. Once your changes have been made, click Publish Note.
Clicking on Delete Note will permanently remove it from the system.