I am going to be in the airport all day on Sept 20th. I have a friend in Florida that can meet us there. Is there a place to sit and talk and get food without going thru security? Since she won't have a ticket.

Once you enter Miami after doing immigration, which is mandatory, you can go visit your friend wherever you want within the United States. If or if you have to go through control again once you return to the airport. You can meet at the same airport outside, and you with your ticket later re-enter. Be careful with time, because there is a lot of control to re-enter. You are supposed to be in transit, you still have to check again, it is not like other countries that have transit zones. USA does not have a transit zone, you are entering your country directly. If you liked the answer give me a like, thank you, good luck

There are many restaurants, cafe and bars in and around the airport. You can select suitable one with Google map.

When you enter on September 20 and already at the airport pass the immigration check and they admit you, you can go everywhere