Hi @ethanmks ,
You can control the order in which the custom fields appear on the ticket page by reordering them inside the HD Ticket Template (the child table where you added your fields). So adjusting the order there will reflect on the ticket view.
You can also refer to the official customization guide here, which explains the available controls for Helpdesk customization:
https://frappe.io/helpdesk/customization-controls
This video may also help: I want to Customize HelpDesk - #5 by Sudhanshu
At the moment, the Helpdesk App UI isn’t fully customizable.