Is it possible to create category for waitlisted appointments?

Navigate to Manage data >> Scheduling code>>Manage waitlist category.

The user can Add/Edit/Delete a waitlist category as per their requirements. The user can use different colors to differentiate the waitlists.

Note: The Waitlist Category Name remains unique.

Once a category has been added, the user needs to go to the patient scheduling page and right click on the appointment and select Waitlist option:

Once the user selects a category then the appointment automatically moves under the waitlist tab having the same color as it's category: