You have every right to defend yourself or another human life using (and not surpassing) equal force. You cannot use deadly force to protect property in Florida. In Florida, as in most places, you cannot use deadly force unless you are 100% convinced that a human life is in immediate jeopardy of great bodily harm or death. I know, because I used to teach law there to, and with active duty police officers. Castle Doctrine explains this in detail. The FL Division of Licensing there can explain even further.