[Vuejs]-Am I able to add more fields to a vuetify calendar event?

No, as far as I know this is not possible.
Not inside vuetify. What is done in some cases is the separation of information using – or, or line breaks. But there is a problem because the long text is not visible.
What can be done today?
Use a dialog to show the details of the event. you can show the details of the event by hovering over the reminder.
See how to do this in the vuetify documentation itself.
https://vuetifyjs.com/en/components/calendars/#click