12 Dec 2022, 21:22

@Stevek Welcome in the UVdesk community!
I hope your time is going well!

You can have custom field with additional add on that is not free.
More info can be found here:

Additional apps that you can add to the open-source UVdesk helpdesk system

To be more specific to your question the component you need would be this:
UVdesk Open Source Custom Fields App