Hi Partner,
You can refer to the following steps:
1.Create one workflow on Appointment entity:

2.Add conditions and create note:

3.Set note Properties:
(1)Copy description field value:

(2)Regarding field:
The value depends on which record you want to associate the created note with, my following screenshot associates it to the related record of the Appointment.

4.Save and Active the workflow.

5.Test:
(1)Run the workflow in appointment:

(2)Check timeline in the related record(Works test) of the appointment:
