Can I legally move with my son out of state if I am still married with no custody order?
No, you need to comply with the Florida Parental Relocation statute, Chapter 61.13001.
If your spouse agrees in writing to your relocation, it would be legal. Otherwise, you need to comply with the statute.
If you are leaving your spouse and plan to take your child, be prepared for a custody suit. It will take you time (6 months) to re establish residency requirements in a new state. In the meantime, the other spouse can file for an ex parte hearing to have the child returned until a court makes a determination. Not a good situation for either party because then you lose the contact with the child until a hearing on the matter can be heard.