There are two ways to create a break in the day if you need to take a few hours off.
The first way is to edit your current availability and break it up into two parts. Let's say you'd like to eat lunch from 12PM-1PM, here's how you would do this:
Create one block avoiding the lunch hour. In this example, it is from 10AM-11AM. If you are editing an existing availability, you can make it a one-time occurrence or apply to all future events for that day of the week.
Create another block avoiding the lunch hour after it. In this example, it is from 12PM-6PM.
https://s3-us-west-2.amazonaws.com/secure.notion-static.com/5c9f28fe-bfd6-44fb-b3fa-54cb2dab2007/Simulator_Screen_Recording_-_iPhone_11_-_2021-05-12_at_22.18.01.mp4
Jupiter automatically works around any events booked in your Google Calendar. To achieve a block from 12PM-1PM, you can create a repeating daily event for lunch 12PM-1PM and it will no longer show up in your available timeslots.