That's not necessarily true - in the US, the federal, state and local governments have broad powers to protect health and safety if necessary. if challenged in court the government would need to show a “compelling government interest” and then prove that the government action was narrowly tailored to meet that goal. However, it's unlikely that the government won't allow people out of their homes to get food, health care, and outdoor exercise. Prohibiting your precious right of assembly in groups without social distancing is one of the most important things that can help fight this thing. It shouldn't need to be an order but based on the Florida spring breakers and people like you who are willing to threaten the health of the rest of us, and the economy, maybe it will need to be an order.