The catalog sits inside Service Management. Open it from the module, pick a question, and the request becomes a ticket rather than a free-text email.
How a request starts
The catalog is the list. The question is the type of request. Raising it creates the ticket that then appears on the agent, team, or all-tickets dashboard, depending on who it is assigned to.
Leaving the question returns you to the list. The ticket itself is worked from the dashboard, including its notes.